Title: WP_Http_Encoding::compress
Published: April 25, 2014
Last modified: April 28, 2025

---

# WP_Http_Encoding::compress( string $raw, int $level = 9, string $supports = null ): string|false

## In this article

 * [Description](https://developer.wordpress.org/reference/classes/wp_http_encoding/compress/?output_format=md#description)
 * [Parameters](https://developer.wordpress.org/reference/classes/wp_http_encoding/compress/?output_format=md#parameters)
 * [Return](https://developer.wordpress.org/reference/classes/wp_http_encoding/compress/?output_format=md#return)
 * [Source](https://developer.wordpress.org/reference/classes/wp_http_encoding/compress/?output_format=md#source)
 * [Changelog](https://developer.wordpress.org/reference/classes/wp_http_encoding/compress/?output_format=md#changelog)

[ Back to top](https://developer.wordpress.org/reference/classes/wp_http_encoding/compress/?output_format=md#wp--skip-link--target)

Compress raw string using the deflate format.

## 󠀁[Description](https://developer.wordpress.org/reference/classes/wp_http_encoding/compress/?output_format=md#description)󠁿

Supports the RFC 1951 standard.

## 󠀁[Parameters](https://developer.wordpress.org/reference/classes/wp_http_encoding/compress/?output_format=md#parameters)󠁿

 `$raw`stringrequired

String to compress.

`$level`intoptional

Compression level, 9 is highest.

Default:`9`

`$supports`stringoptional

Not used. When implemented it will choose the right compression based on what the
server supports.

Default:`null`

## 󠀁[Return](https://developer.wordpress.org/reference/classes/wp_http_encoding/compress/?output_format=md#return)󠁿

 string|false Compressed string on success, false on failure.

## 󠀁[Source](https://developer.wordpress.org/reference/classes/wp_http_encoding/compress/?output_format=md#source)󠁿

    ```php
    public static function compress( $raw, $level = 9, $supports = null ) {
    	return gzdeflate( $raw, $level );
    }
    ```

[View all references](https://developer.wordpress.org/reference/files/wp-includes/class-wp-http-encoding.php/)
[View on Trac](https://core.trac.wordpress.org/browser/tags/6.9.4/src/wp-includes/class-wp-http-encoding.php#L33)
[View on GitHub](https://github.com/WordPress/wordpress-develop/blob/6.9.4/src/wp-includes/class-wp-http-encoding.php#L33-L35)

## 󠀁[Changelog](https://developer.wordpress.org/reference/classes/wp_http_encoding/compress/?output_format=md#changelog)󠁿

| Version | Description | 
| [2.8.0](https://developer.wordpress.org/reference/since/2.8.0/) | Introduced. |

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