Technical SEO

HTTP/3 (QUIC)

Quick Definition

HTTP/3 is the third major version of HTTP, built on QUIC (UDP-based) instead of TCP, eliminating head-of-line blocking and reducing connection-setup latency.

In context

HTTP/3 is widely supported in 2026 by Cloudflare, Fastly, Akamai, and most modern CDNs, plus Chrome, Edge, Safari, and Firefox. The user-visible benefit is faster connections on lossy networks (mobile, hotel Wi-Fi, transit), which directly improves LCP and TTFB on the device experience that matters most. Like HTTP/2 there is no direct ranking signal — the value is real-world Core Web Vitals lift on mobile.

Example

A Canadian B2B SaaS toggled HTTP/3 on Cloudflare and saw mobile TTFB improve ~80ms p75 in CrUX field data over the following month.

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