zip_entry_compressed_size() function in PHP

The zip_entry_compressed_size() function returns the compressed file size of a zip archive entry. This function is part of PHP's legacy ZIP extension and is used to retrieve the size of compressed files within a ZIP archive.

Syntax

zip_entry_compressed_size(zip_entry)

Parameters

• zip_entry − The zip entry resource obtained from zip_read(). Required.

Return Value

Returns the compressed file size in bytes as an integer, or FALSE on failure.

Example

The following example demonstrates how to get the compressed size of files in a ZIP archive ?

<?php
    $zip = zip_open("sample.zip");
    if ($zip) {
        while ($zip_entry = zip_read($zip)) {
            $filename = zip_entry_name($zip_entry);
            $compressed_size = zip_entry_compressedsize($zip_entry);
            echo "File: " . $filename . " - Compressed Size: " . $compressed_size . " bytes<br />";
        }
        zip_close($zip);
    } else {
        echo "Failed to open ZIP file";
    }
?>

File: document.txt - Compressed Size: 90 bytes
File: image.jpg - Compressed Size: 12 bytes
File: data.csv - Compressed Size: 67 bytes

Key Points

• This function is part of the deprecated ZIP extension (removed in PHP 8.0)
• Use ZipArchive class for modern ZIP handling in PHP
• The compressed size is usually smaller than the original file size due to compression
• Always check if the ZIP file opens successfully before processing entries

Conclusion

The zip_entry_compressed_size() function provides the compressed size of ZIP archive entries. For new projects, consider using the modern ZipArchive class instead of these legacy functions.