GZIP Compression Test
Checks the HTML response is served with gzip, brotli or deflate compression.
What this tool checks
Text compression enabled
Checks the HTML response was served with gzip, brotli or deflate compression.
Why it matters: Compressing text resources typically cuts their transfer size by 60–80%, directly speeding up page load.
If it fails: Enable gzip or brotli compression for HTML, CSS, JS and other text responses.
Source: web.dev/articles/reduce-network-payloads-using-text-compression
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