Compression Test (Brotli / gzip)

What does this tool do?

The compression test from eiwen.net checks in real time whether a website or file is delivered with GZIP or Brotli compression - and how much the transfer size is reduced.

• Detects whether your server sends active Content-Encoding (gzip, br or deflate).
• Shows original size and transferred size side by side.
• Automatically calculates the percentage of data reduction.
• Helps optimize loading times and improve Core Web Vitals.

With this free online tool from eiwen.net, you can quickly check whether your server has GZIP or Brotli enabled and whether your website can load faster as a result.

What the test shows

• Content-Encoding (Brotli br, gzip or none) directly from the server headers.
• Real savings: original size vs. transferred size, including percentage.
• Plain response headers - useful for debugging and CDN checks.

Tip: On the command line, you can quickly check with curl -I -H "Accept-Encoding: br" or gzip.

Useful for developers, SEO analysts and site owners who want to improve website performance.

<IfModule mod_brotli.c>
  BrotliCompressionQuality 5
  AddOutputFilterByType BROTLI_COMPRESS text/html text/plain text/css application/javascript application/json
</IfModule>

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