Created
September 2, 2026 00:48
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One HTML file to generate a QR code without any dependencies
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| <!doctype html> | |
| <html lang="en"> | |
| <head> | |
| <meta charset="utf-8"> | |
| <meta name="viewport" content="width=device-width, initial-scale=1"> | |
| <meta name="description" content="A private, dependency-free QR code generator that runs entirely in your browser."> | |
| <title>Offline QR Code Generator</title> | |
| <style> | |
| :root { | |
| color-scheme: light; | |
| --ink: #17221d; | |
| --muted: #647069; | |
| --paper: #f4f0e7; | |
| --card: #fffdf8; | |
| --line: #d8d4c9; | |
| --accent: #176b4d; | |
| --accent-hover: #10543c; | |
| --accent-soft: #e2f0e8; | |
| --danger: #a43a35; | |
| --shadow: 0 24px 60px rgba(31, 48, 39, 0.12); | |
| } | |
| * { | |
| box-sizing: border-box; | |
| } | |
| html { | |
| min-height: 100%; | |
| background: var(--paper); | |
| } | |
| body { | |
| min-height: 100vh; | |
| margin: 0; | |
| color: var(--ink); | |
| background: | |
| linear-gradient(rgba(23, 107, 77, 0.035) 1px, transparent 1px), | |
| linear-gradient(90deg, rgba(23, 107, 77, 0.035) 1px, transparent 1px), | |
| var(--paper); | |
| background-size: 28px 28px; | |
| font-family: ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; | |
| line-height: 1.5; | |
| } | |
| button, | |
| textarea { | |
| font: inherit; | |
| } | |
| button { | |
| -webkit-tap-highlight-color: transparent; | |
| } | |
| .page { | |
| width: min(1080px, calc(100% - 32px)); | |
| margin: 0 auto; | |
| padding: 48px 0; | |
| } | |
| .masthead { | |
| display: flex; | |
| align-items: flex-end; | |
| justify-content: space-between; | |
| gap: 24px; | |
| margin-bottom: 22px; | |
| } | |
| .eyebrow { | |
| margin: 0 0 8px; | |
| color: var(--accent); | |
| font-size: 0.75rem; | |
| font-weight: 800; | |
| letter-spacing: 0.14em; | |
| text-transform: uppercase; | |
| } | |
| h1 { | |
| max-width: 680px; | |
| margin: 0; | |
| font-family: Georgia, "Times New Roman", serif; | |
| font-size: clamp(2.25rem, 5vw, 4.35rem); | |
| font-weight: 500; | |
| letter-spacing: -0.045em; | |
| line-height: 0.98; | |
| } | |
| .privacy-note { | |
| display: inline-flex; | |
| align-items: center; | |
| flex: 0 0 auto; | |
| gap: 9px; | |
| margin: 0 0 5px; | |
| padding: 9px 13px; | |
| border: 1px solid #bdd5c9; | |
| border-radius: 999px; | |
| color: #235e47; | |
| background: rgba(255, 253, 248, 0.72); | |
| font-size: 0.82rem; | |
| font-weight: 700; | |
| } | |
| .privacy-note::before { | |
| width: 8px; | |
| height: 8px; | |
| border-radius: 50%; | |
| background: #2a9a6c; | |
| box-shadow: 0 0 0 4px rgba(42, 154, 108, 0.14); | |
| content: ""; | |
| } | |
| .workspace { | |
| display: grid; | |
| grid-template-columns: minmax(0, 1fr) minmax(320px, 0.78fr); | |
| min-height: 560px; | |
| overflow: hidden; | |
| border: 1px solid var(--line); | |
| border-radius: 24px; | |
| background: var(--card); | |
| box-shadow: var(--shadow); | |
| } | |
| .editor, | |
| .preview { | |
| padding: clamp(26px, 4vw, 46px); | |
| } | |
| .editor { | |
| display: flex; | |
| flex-direction: column; | |
| border-right: 1px solid var(--line); | |
| } | |
| .section-number { | |
| display: inline-grid; | |
| width: 32px; | |
| height: 32px; | |
| margin-bottom: 24px; | |
| place-items: center; | |
| border: 1px solid var(--line); | |
| border-radius: 50%; | |
| color: var(--muted); | |
| font-size: 0.78rem; | |
| font-weight: 800; | |
| } | |
| label { | |
| display: block; | |
| margin-bottom: 10px; | |
| font-size: 1.05rem; | |
| font-weight: 800; | |
| } | |
| .label-note { | |
| display: block; | |
| margin-top: 3px; | |
| color: var(--muted); | |
| font-size: 0.84rem; | |
| font-weight: 500; | |
| } | |
| textarea { | |
| width: 100%; | |
| min-height: 230px; | |
| resize: vertical; | |
| padding: 18px; | |
| border: 1px solid #c8c6bd; | |
| border-radius: 14px; | |
| outline: none; | |
| color: var(--ink); | |
| background: #fff; | |
| font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace; | |
| font-size: 0.95rem; | |
| line-height: 1.6; | |
| transition: border-color 160ms ease, box-shadow 160ms ease; | |
| } | |
| textarea:hover { | |
| border-color: #a8aca6; | |
| } | |
| textarea:focus-visible { | |
| border-color: var(--accent); | |
| box-shadow: 0 0 0 4px rgba(23, 107, 77, 0.14); | |
| } | |
| textarea[aria-invalid="true"] { | |
| border-color: var(--danger); | |
| } | |
| .input-meta { | |
| display: flex; | |
| min-height: 32px; | |
| align-items: flex-start; | |
| justify-content: space-between; | |
| gap: 16px; | |
| margin: 10px 2px 20px; | |
| color: var(--muted); | |
| font-size: 0.78rem; | |
| } | |
| .status { | |
| text-align: right; | |
| } | |
| .status.error { | |
| color: var(--danger); | |
| font-weight: 700; | |
| } | |
| .wifi-guide { | |
| margin: 0 0 22px; | |
| border: 1px solid #c8d8cf; | |
| border-radius: 14px; | |
| background: #f4f8f5; | |
| } | |
| .wifi-guide summary { | |
| padding: 13px 16px; | |
| cursor: pointer; | |
| color: #235e47; | |
| font-size: 0.86rem; | |
| font-weight: 800; | |
| list-style-position: inside; | |
| } | |
| .wifi-guide summary:focus-visible { | |
| border-radius: 13px; | |
| outline: 3px solid rgba(23, 107, 77, 0.22); | |
| outline-offset: 2px; | |
| } | |
| .wifi-guide-body { | |
| padding: 0 16px 16px; | |
| color: var(--muted); | |
| font-size: 0.8rem; | |
| } | |
| .wifi-guide-body p { | |
| margin: 0; | |
| } | |
| .visually-hidden { | |
| position: absolute; | |
| width: 1px; | |
| height: 1px; | |
| overflow: hidden; | |
| clip: rect(0 0 0 0); | |
| clip-path: inset(50%); | |
| white-space: nowrap; | |
| } | |
| .wifi-builder { | |
| min-width: 0; | |
| margin: 13px 0 10px; | |
| padding: 0; | |
| border: 0; | |
| } | |
| .wifi-grid { | |
| display: grid; | |
| grid-template-columns: 1fr 1fr; | |
| gap: 11px; | |
| } | |
| .wifi-field { | |
| min-width: 0; | |
| } | |
| .wifi-field:last-child { | |
| grid-column: 1 / -1; | |
| } | |
| .wifi-field label { | |
| margin: 0 0 5px; | |
| color: var(--ink); | |
| font-size: 0.72rem; | |
| font-weight: 800; | |
| } | |
| .wifi-field input, | |
| .wifi-field select { | |
| width: 100%; | |
| min-height: 42px; | |
| padding: 9px 11px; | |
| border: 1px solid #bfcac3; | |
| border-radius: 9px; | |
| outline: none; | |
| color: var(--ink); | |
| background: #fff; | |
| font-size: 0.82rem; | |
| transition: border-color 160ms ease, box-shadow 160ms ease; | |
| } | |
| .wifi-field input:focus-visible, | |
| .wifi-field select:focus-visible { | |
| border-color: var(--accent); | |
| box-shadow: 0 0 0 3px rgba(23, 107, 77, 0.13); | |
| } | |
| .wifi-field input[aria-invalid="true"] { | |
| border-color: var(--danger); | |
| } | |
| .wifi-field input:disabled { | |
| cursor: not-allowed; | |
| color: #8a938e; | |
| background: #e9eeeb; | |
| } | |
| .wifi-options { | |
| display: flex; | |
| align-items: center; | |
| justify-content: space-between; | |
| gap: 12px; | |
| margin-top: 12px; | |
| } | |
| .wifi-checkbox { | |
| display: inline-flex; | |
| align-items: center; | |
| gap: 8px; | |
| margin: 0; | |
| color: var(--ink); | |
| font-size: 0.78rem; | |
| font-weight: 700; | |
| } | |
| .wifi-checkbox input { | |
| width: 17px; | |
| height: 17px; | |
| margin: 0; | |
| accent-color: var(--accent); | |
| } | |
| .wifi-build { | |
| min-height: 42px; | |
| padding: 9px 14px; | |
| color: #fff; | |
| background: var(--accent); | |
| font-size: 0.78rem; | |
| } | |
| .wifi-build:hover { | |
| background: var(--accent-hover); | |
| } | |
| .wifi-status { | |
| min-height: 18px; | |
| margin-top: 7px !important; | |
| color: var(--muted); | |
| font-size: 0.74rem; | |
| } | |
| .wifi-status.error { | |
| color: var(--danger); | |
| font-weight: 700; | |
| } | |
| .wifi-caution { | |
| padding-top: 10px; | |
| border-top: 1px solid #d6dfd9; | |
| } | |
| .wifi-guide a { | |
| color: var(--accent); | |
| font-weight: 700; | |
| text-underline-offset: 2px; | |
| } | |
| .actions { | |
| display: flex; | |
| gap: 10px; | |
| margin-top: auto; | |
| } | |
| button { | |
| min-height: 46px; | |
| padding: 11px 17px; | |
| border: 1px solid transparent; | |
| border-radius: 11px; | |
| cursor: pointer; | |
| font-weight: 800; | |
| transition: background 160ms ease, border-color 160ms ease, color 160ms ease, transform 100ms ease; | |
| } | |
| button:active:not(:disabled) { | |
| transform: translateY(1px); | |
| } | |
| button:focus-visible { | |
| outline: 3px solid rgba(23, 107, 77, 0.28); | |
| outline-offset: 2px; | |
| } | |
| .primary { | |
| flex: 1; | |
| color: #fff; | |
| background: var(--accent); | |
| } | |
| .primary:hover { | |
| background: var(--accent-hover); | |
| } | |
| .secondary { | |
| color: var(--ink); | |
| border-color: var(--line); | |
| background: transparent; | |
| } | |
| .secondary:hover:not(:disabled) { | |
| border-color: #a8aca6; | |
| background: #f7f5ef; | |
| } | |
| button:disabled { | |
| cursor: not-allowed; | |
| opacity: 0.45; | |
| } | |
| .preview { | |
| display: flex; | |
| flex-direction: column; | |
| align-items: center; | |
| justify-content: center; | |
| background: #eef3ee; | |
| } | |
| .qr-frame { | |
| display: grid; | |
| width: min(100%, 390px); | |
| aspect-ratio: 1; | |
| place-items: center; | |
| padding: clamp(16px, 4vw, 28px); | |
| border: 1px solid #d4ddd7; | |
| border-radius: 20px; | |
| background: #fff; | |
| box-shadow: 0 14px 35px rgba(36, 61, 48, 0.1); | |
| } | |
| canvas { | |
| display: block; | |
| width: 100%; | |
| height: auto; | |
| image-rendering: pixelated; | |
| } | |
| .output-meta { | |
| min-height: 46px; | |
| margin: 20px 0 16px; | |
| color: var(--muted); | |
| font-size: 0.82rem; | |
| text-align: center; | |
| } | |
| .output-meta strong { | |
| display: block; | |
| margin-bottom: 2px; | |
| color: var(--ink); | |
| font-size: 0.9rem; | |
| } | |
| .download { | |
| width: min(100%, 390px); | |
| color: var(--accent); | |
| border-color: #9fc5b3; | |
| background: var(--accent-soft); | |
| } | |
| .download:hover:not(:disabled) { | |
| border-color: #73a98e; | |
| background: #d4e9de; | |
| } | |
| footer { | |
| display: flex; | |
| justify-content: space-between; | |
| gap: 20px; | |
| margin-top: 18px; | |
| color: var(--muted); | |
| font-size: 0.76rem; | |
| } | |
| footer p { | |
| margin: 0; | |
| } | |
| @media (max-width: 760px) { | |
| .page { | |
| width: min(100% - 20px, 620px); | |
| padding: 28px 0; | |
| } | |
| .masthead { | |
| display: block; | |
| } | |
| .privacy-note { | |
| margin-top: 18px; | |
| } | |
| .workspace { | |
| grid-template-columns: 1fr; | |
| } | |
| .editor { | |
| border-right: 0; | |
| border-bottom: 1px solid var(--line); | |
| } | |
| .preview { | |
| min-height: 480px; | |
| } | |
| footer { | |
| display: block; | |
| } | |
| footer p + p { | |
| margin-top: 4px; | |
| } | |
| } | |
| @media (max-width: 430px) { | |
| .editor, | |
| .preview { | |
| padding: 24px 18px; | |
| } | |
| h1 { | |
| font-size: 2.45rem; | |
| } | |
| .actions { | |
| flex-wrap: wrap; | |
| } | |
| .wifi-grid { | |
| grid-template-columns: 1fr; | |
| } | |
| .wifi-field:last-child { | |
| grid-column: auto; | |
| } | |
| .wifi-options { | |
| align-items: stretch; | |
| flex-direction: column; | |
| } | |
| .wifi-build { | |
| width: 100%; | |
| } | |
| .primary { | |
| flex-basis: 100%; | |
| } | |
| .secondary { | |
| flex: 1; | |
| } | |
| .preview { | |
| min-height: 420px; | |
| } | |
| } | |
| @media (prefers-reduced-motion: reduce) { | |
| *, | |
| *::before, | |
| *::after { | |
| scroll-behavior: auto !important; | |
| transition-duration: 0.01ms !important; | |
| } | |
| } | |
| </style> | |
| </head> | |
| <body> | |
| <main class="page"> | |
| <header class="masthead"> | |
| <div> | |
| <p class="eyebrow">Private by design</p> | |
| <h1>Make a QR code.<br>Keep your data.</h1> | |
| </div> | |
| <p class="privacy-note">Works entirely offline</p> | |
| </header> | |
| <section class="workspace" aria-label="QR code generator"> | |
| <form class="editor" id="qr-form" novalidate> | |
| <span class="section-number" aria-hidden="true">01</span> | |
| <label for="qr-input"> | |
| Text or URL | |
| <span class="label-note">Paste a link, message, contact detail, or any UTF-8 text.</span> | |
| </label> | |
| <textarea id="qr-input" spellcheck="false" aria-describedby="input-help input-status">https://example.com/hello</textarea> | |
| <div class="input-meta"> | |
| <span id="input-help">Press Ctrl/⌘ + Enter to generate</span> | |
| <span class="status" id="input-status" role="status" aria-live="polite">25 bytes</span> | |
| </div> | |
| <details class="wifi-guide" open> | |
| <summary>Making a Wi-Fi QR code?</summary> | |
| <div class="wifi-guide-body"> | |
| <p>Enter the network settings and this page will build the Wi-Fi payload for you.</p> | |
| <fieldset class="wifi-builder" id="wifi-builder"> | |
| <legend class="visually-hidden">Wi-Fi network settings</legend> | |
| <div class="wifi-grid"> | |
| <div class="wifi-field"> | |
| <label for="wifi-ssid">Network name (SSID)</label> | |
| <input id="wifi-ssid" type="text" autocomplete="off" placeholder="MyNetwork"> | |
| </div> | |
| <div class="wifi-field"> | |
| <label for="wifi-security">Security</label> | |
| <select id="wifi-security"> | |
| <option value="WPA">WPA / WPA2</option> | |
| <option value="WEP">WEP</option> | |
| <option value="nopass">No password</option> | |
| </select> | |
| </div> | |
| <div class="wifi-field"> | |
| <label for="wifi-password">Password</label> | |
| <input id="wifi-password" type="password" autocomplete="off" placeholder="Network password"> | |
| </div> | |
| </div> | |
| <div class="wifi-options"> | |
| <label class="wifi-checkbox" for="wifi-hidden"> | |
| <input id="wifi-hidden" type="checkbox"> | |
| Hidden network | |
| </label> | |
| <button class="wifi-build" id="wifi-build-button" type="button">Build & Generate</button> | |
| </div> | |
| <p class="wifi-status" id="wifi-status" role="status" aria-live="polite"></p> | |
| </fieldset> | |
| <p>Inside the SSID or password, prefix <code>\</code>, <code>;</code>, <code>,</code>, <code>"</code>, and <code>:</code> with a backslash. Anyone who scans the code can recover its password, so prefer a guest network.</p> | |
| <p class="wifi-caution"><a href="https://dev.to/mycko22/the-technical-guide-to-wifi-qr-codes-implementation-security-and-best-practices-2f2n" target="_blank" rel="noreferrer">Read the Wi-Fi QR guide</a></p> | |
| </div> | |
| </details> | |
| <div class="actions"> | |
| <button class="primary" type="submit">Generate QR Code</button> | |
| <button class="secondary" id="clear-button" type="button">Clear</button> | |
| </div> | |
| </form> | |
| <section class="preview" aria-label="Generated QR code"> | |
| <div class="qr-frame"> | |
| <canvas id="qr-canvas" width="348" height="348" role="img" aria-label="QR code for https://example.com/hello"> | |
| Your browser does not support canvas. | |
| </canvas> | |
| </div> | |
| <p class="output-meta" id="output-meta" aria-live="polite"></p> | |
| <button class="download" id="download-button" type="button" disabled>Download PNG</button> | |
| </section> | |
| </section> | |
| <footer> | |
| <p>No uploads. No tracking. No external libraries.</p> | |
| <p>Error correction: Medium (M)</p> | |
| </footer> | |
| </main> | |
| <script> | |
| "use strict"; | |
| /* | |
| * QR Code Model 2 encoder, adapted from Project Nayuki's QR Code generator. | |
| * Copyright (c) Project Nayuki. Released under the MIT License. | |
| * https://www.nayuki.io/page/qr-code-generator-library | |
| * | |
| * Permission is hereby granted, free of charge, to any person obtaining a copy | |
| * of this software and associated documentation files (the "Software"), to deal | |
| * in the Software without restriction, including without limitation the rights | |
| * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies | |
| * of the Software, and to permit persons to whom the Software is furnished to do | |
| * so, subject to the following conditions: | |
| * | |
| * The above copyright notice and this permission notice shall be included in all | |
| * copies or substantial portions of the Software. | |
| * | |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | |
| * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE | |
| * SOFTWARE. | |
| * | |
| * This page uses byte mode and error correction level M. | |
| */ | |
| class BitBuffer { | |
| constructor() { | |
| this.bits = []; | |
| } | |
| append(value, length) { | |
| if (length < 0 || value >>> length !== 0) { | |
| throw new RangeError("Value does not fit in the requested bit length"); | |
| } | |
| for (let i = length - 1; i >= 0; i--) { | |
| this.bits.push((value >>> i) & 1); | |
| } | |
| } | |
| get length() { | |
| return this.bits.length; | |
| } | |
| } | |
| class QrCode { | |
| static ECC_CODEWORDS_PER_BLOCK = [ | |
| -1, 10, 16, 26, 18, 24, 16, 18, 22, 22, 26, | |
| 30, 22, 22, 24, 24, 28, 28, 26, 26, 26, | |
| 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, | |
| 28, 28, 28, 28, 28, 28, 28, 28, 28, 28 | |
| ]; | |
| static NUM_ERROR_CORRECTION_BLOCKS = [ | |
| -1, 1, 1, 1, 2, 2, 4, 4, 4, 5, 5, | |
| 5, 8, 9, 9, 10, 10, 11, 13, 14, 16, | |
| 17, 17, 18, 20, 21, 23, 25, 26, 28, 29, | |
| 31, 33, 35, 37, 38, 40, 43, 45, 47, 49 | |
| ]; | |
| static encodeText(text) { | |
| const data = Array.from(new TextEncoder().encode(text)); | |
| let version = 1; | |
| for (; version <= 40; version++) { | |
| const countBits = version <= 9 ? 8 : 16; | |
| if (data.length >= 2 ** countBits) continue; | |
| const usedBits = 4 + countBits + data.length * 8; | |
| if (usedBits <= QrCode.getDataCodewords(version) * 8) break; | |
| } | |
| if (version > 40) { | |
| throw new RangeError("That text is too long. Medium error correction supports up to 2,331 UTF-8 bytes."); | |
| } | |
| const dataCodewords = QrCode.makeDataCodewords(data, version); | |
| const allCodewords = QrCode.addErrorCorrection(dataCodewords, version); | |
| return new QrCode(version, allCodewords); | |
| } | |
| constructor(version, codewords) { | |
| this.version = version; | |
| this.size = version * 4 + 17; | |
| this.modules = Array.from({ length: this.size }, () => Array(this.size).fill(false)); | |
| this.isFunction = Array.from({ length: this.size }, () => Array(this.size).fill(false)); | |
| this.drawFunctionPatterns(); | |
| this.drawCodewords(codewords); | |
| let bestMask = 0; | |
| let lowestPenalty = Infinity; | |
| for (let mask = 0; mask < 8; mask++) { | |
| this.applyMask(mask); | |
| this.drawFormatBits(mask); | |
| const penalty = this.getPenaltyScore(); | |
| if (penalty < lowestPenalty) { | |
| bestMask = mask; | |
| lowestPenalty = penalty; | |
| } | |
| this.applyMask(mask); | |
| } | |
| this.applyMask(bestMask); | |
| this.drawFormatBits(bestMask); | |
| this.mask = bestMask; | |
| } | |
| static makeDataCodewords(data, version) { | |
| const capacity = QrCode.getDataCodewords(version) * 8; | |
| const bits = new BitBuffer(); | |
| bits.append(0x4, 4); // Byte mode. | |
| bits.append(data.length, version <= 9 ? 8 : 16); | |
| for (const value of data) bits.append(value, 8); | |
| bits.append(0, Math.min(4, capacity - bits.length)); | |
| bits.append(0, (8 - bits.length % 8) % 8); | |
| const result = []; | |
| for (let i = 0; i < bits.length; i += 8) { | |
| let value = 0; | |
| for (let j = 0; j < 8; j++) value = (value << 1) | bits.bits[i + j]; | |
| result.push(value); | |
| } | |
| for (let pad = 0xEC; result.length < capacity / 8; pad ^= 0xEC ^ 0x11) { | |
| result.push(pad); | |
| } | |
| return result; | |
| } | |
| static addErrorCorrection(data, version) { | |
| const blockCount = QrCode.NUM_ERROR_CORRECTION_BLOCKS[version]; | |
| const eccLength = QrCode.ECC_CODEWORDS_PER_BLOCK[version]; | |
| const rawCodewords = Math.floor(QrCode.getNumRawDataModules(version) / 8); | |
| const shortBlockCount = blockCount - rawCodewords % blockCount; | |
| const shortBlockLength = Math.floor(rawCodewords / blockCount); | |
| const divisor = QrCode.reedSolomonDivisor(eccLength); | |
| const blocks = []; | |
| const eccBlocks = []; | |
| let offset = 0; | |
| for (let block = 0; block < blockCount; block++) { | |
| const dataLength = shortBlockLength - eccLength + (block < shortBlockCount ? 0 : 1); | |
| const part = data.slice(offset, offset + dataLength); | |
| offset += dataLength; | |
| blocks.push(part); | |
| eccBlocks.push(QrCode.reedSolomonRemainder(part, divisor)); | |
| } | |
| const result = []; | |
| const longestDataBlock = shortBlockLength - eccLength + 1; | |
| for (let i = 0; i < longestDataBlock; i++) { | |
| for (const block of blocks) { | |
| if (i < block.length) result.push(block[i]); | |
| } | |
| } | |
| for (let i = 0; i < eccLength; i++) { | |
| for (const block of eccBlocks) result.push(block[i]); | |
| } | |
| if (result.length !== rawCodewords) throw new Error("QR interleaving failed"); | |
| return result; | |
| } | |
| static reedSolomonDivisor(degree) { | |
| const result = Array(degree).fill(0); | |
| result[degree - 1] = 1; | |
| let root = 1; | |
| for (let i = 0; i < degree; i++) { | |
| for (let j = 0; j < result.length; j++) { | |
| result[j] = QrCode.galoisMultiply(result[j], root); | |
| if (j + 1 < result.length) result[j] ^= result[j + 1]; | |
| } | |
| root = QrCode.galoisMultiply(root, 0x02); | |
| } | |
| return result; | |
| } | |
| static reedSolomonRemainder(data, divisor) { | |
| const result = Array(divisor.length).fill(0); | |
| for (const value of data) { | |
| const factor = value ^ result.shift(); | |
| result.push(0); | |
| for (let i = 0; i < result.length; i++) { | |
| result[i] ^= QrCode.galoisMultiply(divisor[i], factor); | |
| } | |
| } | |
| return result; | |
| } | |
| static galoisMultiply(x, y) { | |
| let result = 0; | |
| for (let i = 7; i >= 0; i--) { | |
| result = (result << 1) ^ ((result >>> 7) * 0x11D); | |
| result ^= ((y >>> i) & 1) * x; | |
| } | |
| return result; | |
| } | |
| static getDataCodewords(version) { | |
| return Math.floor(QrCode.getNumRawDataModules(version) / 8) | |
| - QrCode.ECC_CODEWORDS_PER_BLOCK[version] * QrCode.NUM_ERROR_CORRECTION_BLOCKS[version]; | |
| } | |
| static getNumRawDataModules(version) { | |
| let result = (16 * version + 128) * version + 64; | |
| if (version >= 2) { | |
| const alignmentCount = Math.floor(version / 7) + 2; | |
| result -= (25 * alignmentCount - 10) * alignmentCount - 55; | |
| if (version >= 7) result -= 36; | |
| } | |
| return result; | |
| } | |
| drawFunctionPatterns() { | |
| for (let i = 0; i < this.size; i++) { | |
| this.setFunctionModule(6, i, i % 2 === 0); | |
| this.setFunctionModule(i, 6, i % 2 === 0); | |
| } | |
| this.drawFinderPattern(3, 3); | |
| this.drawFinderPattern(this.size - 4, 3); | |
| this.drawFinderPattern(3, this.size - 4); | |
| const positions = this.getAlignmentPatternPositions(); | |
| const last = positions.length - 1; | |
| for (let i = 0; i < positions.length; i++) { | |
| for (let j = 0; j < positions.length; j++) { | |
| if ((i === 0 && j === 0) || (i === 0 && j === last) || (i === last && j === 0)) continue; | |
| this.drawAlignmentPattern(positions[i], positions[j]); | |
| } | |
| } | |
| this.drawFormatBits(0); | |
| this.drawVersion(); | |
| } | |
| drawFinderPattern(centerX, centerY) { | |
| for (let dy = -4; dy <= 4; dy++) { | |
| for (let dx = -4; dx <= 4; dx++) { | |
| const x = centerX + dx; | |
| const y = centerY + dy; | |
| if (x < 0 || y < 0 || x >= this.size || y >= this.size) continue; | |
| const distance = Math.max(Math.abs(dx), Math.abs(dy)); | |
| this.setFunctionModule(x, y, distance !== 2 && distance !== 4); | |
| } | |
| } | |
| } | |
| drawAlignmentPattern(centerX, centerY) { | |
| for (let dy = -2; dy <= 2; dy++) { | |
| for (let dx = -2; dx <= 2; dx++) { | |
| this.setFunctionModule(centerX + dx, centerY + dy, Math.max(Math.abs(dx), Math.abs(dy)) !== 1); | |
| } | |
| } | |
| } | |
| getAlignmentPatternPositions() { | |
| if (this.version === 1) return []; | |
| const count = Math.floor(this.version / 7) + 2; | |
| const step = Math.floor((this.version * 8 + count * 3 + 5) / (count * 4 - 4)) * 2; | |
| const result = [6]; | |
| for (let position = this.size - 7; result.length < count; position -= step) { | |
| result.splice(1, 0, position); | |
| } | |
| return result; | |
| } | |
| drawFormatBits(mask) { | |
| const data = mask; // Error correction M has format bits 00. | |
| let remainder = data; | |
| for (let i = 0; i < 10; i++) remainder = (remainder << 1) ^ ((remainder >>> 9) * 0x537); | |
| const bits = ((data << 10) | remainder) ^ 0x5412; | |
| const bit = index => ((bits >>> index) & 1) !== 0; | |
| for (let i = 0; i <= 5; i++) this.setFunctionModule(8, i, bit(i)); | |
| this.setFunctionModule(8, 7, bit(6)); | |
| this.setFunctionModule(8, 8, bit(7)); | |
| this.setFunctionModule(7, 8, bit(8)); | |
| for (let i = 9; i < 15; i++) this.setFunctionModule(14 - i, 8, bit(i)); | |
| for (let i = 0; i < 8; i++) this.setFunctionModule(this.size - 1 - i, 8, bit(i)); | |
| for (let i = 8; i < 15; i++) this.setFunctionModule(8, this.size - 15 + i, bit(i)); | |
| this.setFunctionModule(8, this.size - 8, true); | |
| } | |
| drawVersion() { | |
| if (this.version < 7) return; | |
| let remainder = this.version; | |
| for (let i = 0; i < 12; i++) remainder = (remainder << 1) ^ ((remainder >>> 11) * 0x1F25); | |
| const bits = (this.version << 12) | remainder; | |
| for (let i = 0; i < 18; i++) { | |
| const value = ((bits >>> i) & 1) !== 0; | |
| const a = this.size - 11 + i % 3; | |
| const b = Math.floor(i / 3); | |
| this.setFunctionModule(a, b, value); | |
| this.setFunctionModule(b, a, value); | |
| } | |
| } | |
| setFunctionModule(x, y, dark) { | |
| this.modules[y][x] = dark; | |
| this.isFunction[y][x] = true; | |
| } | |
| drawCodewords(codewords) { | |
| let bitIndex = 0; | |
| for (let right = this.size - 1; right >= 1; right -= 2) { | |
| if (right === 6) right = 5; | |
| for (let vertical = 0; vertical < this.size; vertical++) { | |
| const upward = ((right + 1) & 2) === 0; | |
| const y = upward ? this.size - 1 - vertical : vertical; | |
| for (let column = 0; column < 2; column++) { | |
| const x = right - column; | |
| if (this.isFunction[y][x] || bitIndex >= codewords.length * 8) continue; | |
| this.modules[y][x] = ((codewords[bitIndex >>> 3] >>> (7 - (bitIndex & 7))) & 1) !== 0; | |
| bitIndex++; | |
| } | |
| } | |
| } | |
| if (bitIndex !== codewords.length * 8) throw new Error("QR data placement failed"); | |
| } | |
| applyMask(mask) { | |
| for (let y = 0; y < this.size; y++) { | |
| for (let x = 0; x < this.size; x++) { | |
| if (!this.isFunction[y][x] && QrCode.maskBit(mask, x, y)) { | |
| this.modules[y][x] = !this.modules[y][x]; | |
| } | |
| } | |
| } | |
| } | |
| static maskBit(mask, x, y) { | |
| switch (mask) { | |
| case 0: return (x + y) % 2 === 0; | |
| case 1: return y % 2 === 0; | |
| case 2: return x % 3 === 0; | |
| case 3: return (x + y) % 3 === 0; | |
| case 4: return (Math.floor(x / 3) + Math.floor(y / 2)) % 2 === 0; | |
| case 5: return x * y % 2 + x * y % 3 === 0; | |
| case 6: return (x * y % 2 + x * y % 3) % 2 === 0; | |
| case 7: return ((x + y) % 2 + x * y % 3) % 2 === 0; | |
| default: throw new RangeError("Invalid QR mask"); | |
| } | |
| } | |
| getPenaltyScore() { | |
| let score = 0; | |
| const scoreRuns = line => { | |
| let total = 0; | |
| let runColor = line[0]; | |
| let runLength = 1; | |
| for (let i = 1; i <= line.length; i++) { | |
| if (i < line.length && line[i] === runColor) { | |
| runLength++; | |
| } else { | |
| if (runLength >= 5) total += 3 + runLength - 5; | |
| if (i < line.length) { | |
| runColor = line[i]; | |
| runLength = 1; | |
| } | |
| } | |
| } | |
| return total; | |
| }; | |
| const finderA = "00001011101"; | |
| const finderB = "10111010000"; | |
| const scoreFinderPatterns = line => { | |
| const text = line.map(value => value ? "1" : "0").join(""); | |
| let total = 0; | |
| for (let i = 0; i <= text.length - 11; i++) { | |
| const window = text.slice(i, i + 11); | |
| if (window === finderA || window === finderB) total += 40; | |
| } | |
| return total; | |
| }; | |
| for (let y = 0; y < this.size; y++) { | |
| score += scoreRuns(this.modules[y]); | |
| score += scoreFinderPatterns(this.modules[y]); | |
| } | |
| for (let x = 0; x < this.size; x++) { | |
| const column = this.modules.map(row => row[x]); | |
| score += scoreRuns(column); | |
| score += scoreFinderPatterns(column); | |
| } | |
| for (let y = 0; y < this.size - 1; y++) { | |
| for (let x = 0; x < this.size - 1; x++) { | |
| const value = this.modules[y][x]; | |
| if (this.modules[y][x + 1] === value | |
| && this.modules[y + 1][x] === value | |
| && this.modules[y + 1][x + 1] === value) { | |
| score += 3; | |
| } | |
| } | |
| } | |
| let dark = 0; | |
| for (const row of this.modules) for (const value of row) dark += value ? 1 : 0; | |
| const total = this.size * this.size; | |
| score += (Math.ceil(Math.abs(dark * 20 - total * 10) / total) - 1) * 10; | |
| return score; | |
| } | |
| } | |
| const input = document.getElementById("qr-input"); | |
| const form = document.getElementById("qr-form"); | |
| const clearButton = document.getElementById("clear-button"); | |
| const downloadButton = document.getElementById("download-button"); | |
| const canvas = document.getElementById("qr-canvas"); | |
| const inputStatus = document.getElementById("input-status"); | |
| const outputMeta = document.getElementById("output-meta"); | |
| const wifiBuilder = document.getElementById("wifi-builder"); | |
| const wifiSsid = document.getElementById("wifi-ssid"); | |
| const wifiSecurity = document.getElementById("wifi-security"); | |
| const wifiPassword = document.getElementById("wifi-password"); | |
| const wifiHidden = document.getElementById("wifi-hidden"); | |
| const wifiBuildButton = document.getElementById("wifi-build-button"); | |
| const wifiStatus = document.getElementById("wifi-status"); | |
| const context = canvas.getContext("2d"); | |
| const MAX_BYTES = 2331; | |
| let currentQr = null; | |
| function getByteLength(text) { | |
| return new TextEncoder().encode(text).length; | |
| } | |
| function updateInputStatus(message = "", isError = false) { | |
| const bytes = getByteLength(input.value); | |
| inputStatus.textContent = message || `${bytes.toLocaleString()} ${bytes === 1 ? "byte" : "bytes"}`; | |
| inputStatus.classList.toggle("error", isError); | |
| input.setAttribute("aria-invalid", String(isError)); | |
| } | |
| function setWifiStatus(message = "", isError = false) { | |
| wifiStatus.textContent = message; | |
| wifiStatus.classList.toggle("error", isError); | |
| } | |
| function escapeWifiValue(value) { | |
| return value.replace(/[\\;,":]/g, "\\$&"); | |
| } | |
| function updateWifiPasswordState() { | |
| const isOpen = wifiSecurity.value === "nopass"; | |
| wifiPassword.disabled = isOpen; | |
| wifiPassword.placeholder = isOpen ? "Not needed for an open network" : "Network password"; | |
| wifiPassword.setAttribute("aria-invalid", "false"); | |
| setWifiStatus(); | |
| } | |
| function buildWifiQr() { | |
| const ssid = wifiSsid.value; | |
| const security = wifiSecurity.value; | |
| const isOpen = security === "nopass"; | |
| const password = wifiPassword.value; | |
| wifiSsid.setAttribute("aria-invalid", String(ssid.length === 0)); | |
| wifiPassword.setAttribute("aria-invalid", String(!isOpen && password.length === 0)); | |
| if (ssid.length === 0) { | |
| setWifiStatus("Enter the Wi-Fi network name.", true); | |
| wifiSsid.focus(); | |
| return; | |
| } | |
| if (!isOpen && password.length === 0) { | |
| setWifiStatus("Enter the Wi-Fi password, or choose No password.", true); | |
| wifiPassword.focus(); | |
| return; | |
| } | |
| const fields = [`WIFI:T:${security}`, `S:${escapeWifiValue(ssid)}`]; | |
| if (!isOpen) fields.push(`P:${escapeWifiValue(password)}`); | |
| fields.push(`H:${wifiHidden.checked}`); | |
| input.value = `${fields.join(";")};;`; | |
| setWifiStatus("Wi-Fi payload built and QR code generated."); | |
| generate(); | |
| } | |
| function clearCanvas() { | |
| canvas.width = 348; | |
| canvas.height = 348; | |
| context.fillStyle = "#ffffff"; | |
| context.fillRect(0, 0, canvas.width, canvas.height); | |
| context.fillStyle = "#dfe7e2"; | |
| const cell = 12; | |
| for (let y = 3; y < 26; y++) { | |
| for (let x = 3; x < 26; x++) { | |
| if ((x * 3 + y * 5) % 7 === 0) context.fillRect(x * cell, y * cell, cell, cell); | |
| } | |
| } | |
| canvas.setAttribute("aria-label", "No QR code generated"); | |
| } | |
| function renderQr(qr, label) { | |
| const quietZone = 4; | |
| const moduleCount = qr.size + quietZone * 2; | |
| const scale = Math.max(4, Math.floor(1024 / moduleCount)); | |
| const imageSize = moduleCount * scale; | |
| canvas.width = imageSize; | |
| canvas.height = imageSize; | |
| context.imageSmoothingEnabled = false; | |
| context.fillStyle = "#ffffff"; | |
| context.fillRect(0, 0, imageSize, imageSize); | |
| context.fillStyle = "#000000"; | |
| for (let y = 0; y < qr.size; y++) { | |
| for (let x = 0; x < qr.size; x++) { | |
| if (qr.modules[y][x]) { | |
| context.fillRect((x + quietZone) * scale, (y + quietZone) * scale, scale, scale); | |
| } | |
| } | |
| } | |
| canvas.setAttribute("aria-label", `QR code for ${label}`); | |
| } | |
| function generate() { | |
| const text = input.value; | |
| if (text.length === 0) { | |
| currentQr = null; | |
| clearCanvas(); | |
| updateInputStatus("Enter some text to generate a QR code.", true); | |
| outputMeta.innerHTML = ""; | |
| downloadButton.disabled = true; | |
| return; | |
| } | |
| try { | |
| const qr = QrCode.encodeText(text); | |
| currentQr = qr; | |
| const label = text.startsWith("WIFI:") | |
| ? "Wi-Fi network settings" | |
| : text.length > 80 ? `${text.slice(0, 77)}…` : text; | |
| renderQr(qr, label); | |
| updateInputStatus(); | |
| outputMeta.innerHTML = `<strong>Ready to scan</strong>Version ${qr.version} · ${qr.size} × ${qr.size} modules · Mask ${qr.mask}`; | |
| downloadButton.disabled = false; | |
| } catch (error) { | |
| currentQr = null; | |
| clearCanvas(); | |
| updateInputStatus(error instanceof RangeError ? error.message : "Unable to generate this QR code.", true); | |
| outputMeta.innerHTML = ""; | |
| downloadButton.disabled = true; | |
| if (!(error instanceof RangeError)) console.error(error); | |
| } | |
| } | |
| form.addEventListener("submit", event => { | |
| event.preventDefault(); | |
| generate(); | |
| }); | |
| input.addEventListener("input", () => { | |
| const bytes = getByteLength(input.value); | |
| if (bytes > MAX_BYTES) { | |
| updateInputStatus(`${bytes.toLocaleString()} bytes · exceeds the ${MAX_BYTES.toLocaleString()}-byte limit`, true); | |
| } else { | |
| updateInputStatus(); | |
| } | |
| }); | |
| input.addEventListener("keydown", event => { | |
| if (event.key === "Enter" && (event.ctrlKey || event.metaKey)) { | |
| event.preventDefault(); | |
| generate(); | |
| } | |
| }); | |
| wifiBuildButton.addEventListener("click", buildWifiQr); | |
| wifiBuilder.addEventListener("keydown", event => { | |
| if (event.key === "Enter" && event.target.matches("input:not([type=checkbox]), select")) { | |
| event.preventDefault(); | |
| buildWifiQr(); | |
| } | |
| }); | |
| wifiSecurity.addEventListener("change", updateWifiPasswordState); | |
| wifiSsid.addEventListener("input", () => { | |
| wifiSsid.setAttribute("aria-invalid", "false"); | |
| setWifiStatus(); | |
| }); | |
| wifiPassword.addEventListener("input", () => { | |
| wifiPassword.setAttribute("aria-invalid", "false"); | |
| setWifiStatus(); | |
| }); | |
| clearButton.addEventListener("click", () => { | |
| input.value = ""; | |
| currentQr = null; | |
| clearCanvas(); | |
| updateInputStatus(); | |
| outputMeta.innerHTML = ""; | |
| downloadButton.disabled = true; | |
| wifiSsid.value = ""; | |
| wifiSecurity.value = "WPA"; | |
| wifiPassword.value = ""; | |
| wifiHidden.checked = false; | |
| wifiSsid.setAttribute("aria-invalid", "false"); | |
| updateWifiPasswordState(); | |
| input.focus(); | |
| }); | |
| downloadButton.addEventListener("click", () => { | |
| if (!currentQr) return; | |
| const link = document.createElement("a"); | |
| link.download = "qr-code.png"; | |
| link.href = canvas.toDataURL("image/png"); | |
| link.click(); | |
| }); | |
| updateWifiPasswordState(); | |
| generate(); | |
| </script> | |
| </body> | |
| </html> |
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