How to Use PHP filemtime to Retrieve File Modification Time

PHP's filemtime function returns the last modification time of a file as a Unix timestamp. By passing the file path as an argument, developers can obtain this timestamp and then format it using date for human‑readable output.

Example 1 shows how to define a file path, call filemtime, and echo the formatted modification time.

$file_path = 'path/to/file.txt'; // 文件路径
$modification_time = filemtime($file_path); // 获取文件的最后修改时间

echo "文件最后修改时间：" . date('Y-m-d H:i:s', $modification_time); // 将时间戳转换为可读格式

Example 2 demonstrates processing multiple files by storing their paths in an array, iterating with foreach, retrieving each file's modification time, and printing the file name together with the formatted timestamp.

$files = array(
    'path/to/file1.txt',
    'path/to/file2.txt',
    'path/to/file3.txt'
);

foreach ($files as $file_path) {
    $modification_time = filemtime($file_path);
    echo "文件：'" . basename($file_path) . "' 最后修改时间：" . date('Y-m-d H:i:s', $modification_time) . "<br>";
}

The article concludes that using filemtime combined with date provides a straightforward way to obtain and display file modification times in PHP.