UUID (hex) to base62 and vice-versa

Base62.php

<?php


class Base62
{
	const BASE_OCT = 8;
	const BASE_DEC = 10;
	const BASE_HEX = 16;
	const BASE_62 = 62;

	const POOL = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';


	/**
	 * @param int $num
	 * @param int $inputBase
	 * @param int $outputBase
	 * @return string
	 */
	public static function convert($num, $inputBase = self::BASE_DEC, $outputBase = self::BASE_62)
	{
		if (!extension_loaded('gmp')) {
			throw new LogicException('Please enable GMP extension to use base62 conversion');
		}

		if ($inputBase === 16) {
			$num = preg_replace('/[^0-9A-Fa-f]/i', '', $num);  // remove any non-hex characters
		}

		$gmpNum = gmp_init($num, $inputBase);
		$gmpBase = gmp_init($outputBase, 10);

		list($quotient, $remainder) = gmp_div_qr($gmpNum, $gmpBase);
		$out = self::POOL[gmp_intval($remainder)];

		while (gmp_intval($quotient)) {
			list($quotient, $remainder) = gmp_div_qr($quotient, $gmpBase);
			$out = self::POOL[gmp_intval($remainder)] . $out;
		}

		return $out;
	}
}

test.php

<?php

require_once __DIR__ . '/Base62.php';
?>

<style>
	body { margin:1rem auto; max-width:36rem; }
	p { text-align:center; }
	pre { white-space:pre-wrap; word-wrap:break-word; }
	td { border:1px solid lightgray; min-width:10rem; padding:0.25rem 1rem; }
</style>


<pre>
<table>
	<tr><th><h2>dec</h2> </th><th>hex</th> <th>base62</th></tr>
	<?php $decNums = [
		'000',
		'001',
		'002',
		'003',
		'010',
		'015',
		'016',
		'017',
		'061',
		'062',
		'063',
		'064',
	] ?>
	<?php foreach ($decNums as $num) { ?>
		<tr>
			<td><?= $num ?></td>
			<td><?= Base62::convert($num, Base62::BASE_DEC, Base62::BASE_HEX) ?></td>
			<td><?= Base62::convert($num) ?></td>
		</tr>
	<?php } ?>
</table>

<table>
	<tr><th><h2>hex</h2></th> <th>dec</th> <th>base62</th></tr>
	<?php $hexNums = [
		'000',
		'001',
		'002',
		'003',
		'00a',
		'00f',
		'010',
		'011',
		'03d',
		'03e',
		'03f',
		'040',
		'ab1ba25a-3956',
		'4d1b-858b',
		'adcdd132e691',
	] ?>
	<?php foreach ($hexNums as $num) { ?>
		<tr>
			<td><?= $num ?></td>
			<td><?= Base62::convert($num, Base62::BASE_HEX, Base62::BASE_DEC) ?></td>
			<td><?= Base62::convert($num, Base62::BASE_HEX) ?></td>
		</tr>
	<?php } ?>
</table>

<table>
	<tr><th><h2>base62</h2></th> <th>dec</th> <th>hex</th></tr>
	<?php $base62Nums = [
		'0',
		'1',
		'2',
		'3',
		'A',
		'F',
		'G',
		'H',
		'z',
		'10',
		'11',
		'12',
		'rQDxyr5S',
		'1PY1H9',
		'sGPeBjO5',
	] ?>
	<?php foreach ($base62Nums as $num) { ?>
		<tr>
			<td><?= $num ?></td>
			<td><?= Base62::convert($num, Base62::BASE_62, Base62::BASE_DEC) ?></td>
			<td><?= Base62::convert($num, Base62::BASE_62, Base62::BASE_HEX) ?></td>
		</tr>
	<?php } ?>
</table>