How to Use GZIP Compression Checker

About this tool

Test whether a website uses GZIP or Brotli compression and how much it saves.

How to use GZIP Compression Checker

1. Enter the page URL.
2. Click Test compression.
3. Check the result and savings. If compression is off, turn it on in your server or CDN.

Worked example

A 120 KB HTML page usually shrinks to about 25 KB with GZIP, a saving of around 80%. That makes the page noticeably faster on slow mobile connections.

GZIP or Brotli?

Brotli usually compresses text 15–20% better than GZIP and is supported by all modern browsers. Servers fall back to GZIP for older clients.

Should images be compressed with GZIP?

No. JPEG, PNG and WebP are already compressed. Compression helps HTML, CSS, JavaScript, JSON and SVG.

Put this guide into practice

• GZIP Compression Checker — Test whether a website uses GZIP or Brotli compression and how much it saves.