PHP get file size from remote URL without download

get.php

<?php

    $url = 'https://speed.hetzner.de/100MB.bin';
    $url = 'https://speed.hetzner.de/100MB.bin';
    $url = 'https://speed.hetzner.de/10GB.bin';

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_HEADER, true);
    curl_setopt($ch, CURLOPT_NOBODY, true);
    curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "GET");
    curl_exec($ch);
    $size = curl_getinfo($ch, CURLINFO_CONTENT_LENGTH_DOWNLOAD);
    curl_close($ch);

    var_dump(($size));