Compression & HTTP/2-3 Checker — is your delivery modern and efficient?
Compression and modern protocols make your site faster to deliver — smaller transfers and more efficient connections, for free. This check looks at whether your responses are compressed (gzip or Brotli) and served over modern protocols (HTTP/2 or HTTP/3). These are well-established, low-effort wins that cut how much data travels and how efficiently it's delivered, benefiting every user and crawler.
Updated June 2026 · Technical SEO & GEO · Part of Infrastructure, Bots & DNS
Check compression & protocol
Paste a URL — GEObubbly checks whether your site uses compression and modern HTTP/2 or HTTP/3 delivery.
✓ Free check✓ 1 signal✓ No signup required
In short: Serve text resources with compression (gzip or Brotli) and use HTTP/2 or HTTP/3 instead of HTTP/1.1. Both are typically configuration toggles with no downside.
What does the compression & protocol check look for?
It checks how efficiently your responses are compressed and delivered. Specifically:
Compression — whether text resources (HTML, CSS, JS) are compressed with gzip or, better, Brotli.
HTTP version — whether the site is served over HTTP/2 or HTTP/3 rather than the older HTTP/1.1.
Efficiency — whether the delivery setup minimises transfer size and connection overhead.
Compression plus HTTP/2 or HTTP/3 passes; one present but not the other is a warning; no compression and legacy HTTP/1.1 is a fail.
How is it evaluated, and how is it scored?
GEObubbly inspects the response headers and protocol of the live connection to check compression and HTTP version. It's an extended Infrastructure check that runs partially, since it observes the live delivery.
Criteria: Pass — compressed over HTTP/2/3. Warning — one but not both. Fail — uncompressed over HTTP/1.1.
Why compression and modern protocols matter for SEO and GEO
Two delivery-layer improvements make your site meaningfully faster with essentially no downside. Compression: text-based resources like HTML, CSS and JavaScript compress extremely well, and enabling gzip — or better, Brotli, which typically compresses smaller — can cut their transfer size dramatically, so pages download faster, especially on slower connections. Modern protocols:HTTP/2 and HTTP/3 deliver resources far more efficiently than the legacy HTTP/1.1, with features like multiplexing and, for HTTP/3, faster, more resilient connections over QUIC. Both are widely supported and usually a configuration toggle rather than a code change. The payoff is reduced transfer size and connection overhead, which improves loading speed and Core Web Vitals, and makes your site cheaper for crawlers to fetch — so engines, including AI crawlers, can cover more per visit.
How this check scores
Pass:Compressed (gzip/Brotli) over HTTP/2 or HTTP/3.
Warning:One of compression or modern HTTP, not both.
Fail:Uncompressed delivery over legacy HTTP/1.1.
FAQ
HTTP compression shrinks the size of text-based responses — HTML, CSS, JavaScript — before they're sent to the browser, which then decompresses them. Gzip is the long-established standard, and Brotli is a newer algorithm that typically achieves smaller sizes, especially for text. Because these resources compress very well, enabling compression can cut transfer sizes substantially, meaning pages download faster and use less bandwidth — a noticeable benefit on slower or mobile connections. It's usually a simple server or CDN setting to turn on, and it's one of the easiest performance wins available with no downside to content.
Audit your page across all 9 checks in Infrastructure, Bots & DNS