Compression Checker

Check if your server is serving compressed files (Gzip/Brotli) to speed up your website.

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We'll check for Gzip, Brotli, and Deflate headers.

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Why Compression Matters

Web compression is one of the easiest and most effective ways to speed up your website. By compressing files (HTML, CSS, JS) on the server before sending them to the browser, you can reduce file sizes by up to 70%.

Gzip

The industry standard. Supported by almost every browser and server. It's fast and effective for most text-based files.

Brotli

The modern successor. Developed by Google, Brotli offers 15-20% better compression than Gzip. It's the best choice for static assets.

How to Enable Compression

Apache (.htaccess)

<IfModule mod_deflate.c>
  AddOutputFilterByType DEFLATE text/html text/plain text/xml text/css application/javascript
</IfModule>

Nginx (nginx.conf)

gzip on;
gzip_types text/plain text/css application/json application/javascript text/xml application/xml;
gzip_proxied any;

About This Tool

The Compression Checker is a free utility designed to help webmasters, developers, and SEO professionals verify that their web servers are correctly configured to serve compressed content.

We send a request to your URL with specific headers (Accept-Encoding: gzip, deflate, br) to simulate a modern browser. We then analyze the response headers to see if the server replies with a Content-Encoding header, confirming that compression is active.

Frequently Asked Questions

What is the difference between Gzip and Brotli?

Gzip is older and widely supported. Brotli is newer, offers better compression ratios (smaller files), but requires HTTPS to work in most browsers. Ideally, your server should support both, prioritizing Brotli.

Does compression affect images?

Generally, no. Formats like JPEG, PNG, and WebP are already compressed. Gzip/Brotli are most effective on text-based files like HTML, CSS, JavaScript, and JSON.

Why is my site not compressed?

Common reasons include: missing server modules (mod_deflate for Apache, ngx_http_gzip_module for Nginx), misconfiguration in .htaccess or nginx.conf, or using a CDN that isn't configured to compress origin content.

How much speed improvement can I expect?

For text-heavy pages, compression can reduce file size by 70%, significantly improving First Contentful Paint (FCP) and overall load time, especially on mobile networks.

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