HTTP/3 Browser and Server Support Status
Current browser and server support for HTTP/3 and QUIC. Learn which browsers, web servers, CDNs, and cloud providers support HTTP/3 today.
Detailed Explanation
HTTP/3 Support Status
HTTP/3 (RFC 9114, published June 2022) has rapidly gained support across browsers, servers, and CDNs.
Browser Support
As of early 2026, HTTP/3 is supported by all major browsers:
| Browser | Version | Release Date | Notes |
|---|---|---|---|
| Chrome | 87+ | Nov 2020 | Enabled by default |
| Firefox | 88+ | Apr 2021 | Enabled by default |
| Edge | 87+ | Nov 2020 | Chromium-based |
| Safari | 14+ | Sep 2020 | macOS/iOS |
| Opera | 74+ | Dec 2020 | Chromium-based |
Server Support
| Server | Status | Notes |
|---|---|---|
| Nginx | Experimental | Since 1.25.0 with quiche or ngtcp2 |
| Caddy | Stable | Native QUIC support via quic-go |
| LiteSpeed | Stable | Full production support |
| Node.js | Experimental | Via undici or quiche bindings |
| Apache | In progress | mod_h3 under development |
| IIS | Supported | Windows Server 2022+ |
CDN and Cloud Support
| Provider | Status |
|---|---|
| Cloudflare | Enabled by default for all plans |
| AWS CloudFront | Supported since Nov 2022 |
| Google Cloud CDN | Supported |
| Fastly | Supported via H3 beta |
| Akamai | Supported |
| Azure CDN | Supported since 2023 |
Adoption Statistics
As of 2026, approximately 30-35% of all web traffic uses HTTP/3 (measured by W3Techs and HTTP Archive). Adoption is highest on mobile where QUIC's benefits are most pronounced.
Fallback Mechanism
Browsers discover HTTP/3 support via the Alt-Svc response header or HTTPS DNS records. If QUIC is blocked (some enterprise networks, restrictive firewalls), the browser automatically falls back to HTTP/2 or HTTP/1.1. This makes HTTP/3 deployment safe — users who cannot use it simply get the previous protocol.
Use Case
DevOps teams planning HTTP/3 deployment need to verify that their infrastructure chain supports QUIC: load balancers, reverse proxies, firewalls (UDP 443), and monitoring tools. The fallback mechanism makes deployment low-risk, but understanding the current support landscape helps set realistic adoption expectations.