filesize(): size of a specified file in bytes

echo filesize('test.htm');

130

Size of all files of directory

$ar=scandir('.'); // current dir
while (list ($key, $val) = each ($ar)) { 
echo $val . filesize($val). " bytes " ;
echo "<br>";
}

Handling Non-Existent Files with filesize()

if (!file_exists('sample.txt')) {
    echo 'File does not exist';
} else {
    echo 'File size: ' . filesize('sample.txt') . ' bytes';
}

Example: Convert Bytes to KB, MB, GB Automatically

function format_size($size) {
    $units = ['B', 'KB', 'MB', 'GB', 'TB'];
    $unit_index = 0;
    while ($size >= 1024 && $unit_index < count($units) - 1) {
        $size /= 1024;
        $unit_index++;
    }
    return round($size, 2) . ' ' . $units[$unit_index];
}

$file_size = filesize('sample.txt');
echo 'Formatted size: ' . format_size($file_size);

Use Case: Handling Multiple File Sizes in a Directory

$dir = 'path/to/directory';
$files = scandir($dir);
foreach ($files as $file) {
    if (is_file("$dir/$file")) {
        echo "$file: " . filesize("$dir/$file") . " bytes
";
    }
}

Example: Using filesize() with a Remote URL

$url = 'http://example.com/sample.jpg';
$headers = get_headers($url, 1);
if (isset($headers['Content-Length'])) {
    echo 'File size: ' . $headers['Content-Length'] . ' bytes';
} else {
    echo 'Unable to determine file size.';
}

Example: Checking File Size in a Different Directory

$file_path = '/var/www/html/sample.txt';
if (file_exists($file_path)) {
    echo 'File size: ' . filesize($file_path) . ' bytes';
} else {
    echo 'File does not exist';
}

Example: Handling Large Files

$file_path = 'large_file.zip';
if (file_exists($file_path)) {
    $file_size = filesize($file_path);
    echo $file_size > 1_000_000 ? 'File size is greater than 1MB' : 'File size is less than 1MB';
} else {
    echo 'File does not exist';
}

Subhendu Mohapatra

Author

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