HTTP/3 Check - QUIC Browser Test

Test your website and browser for HTTP/3 and QUIC protocol support online - Free browser check tool

Public HTTPS endpoints on port 443 only. Checks are rate limited; please wait if the checker is busy. TLS certificates must be valid.

cloudflare.com

check_circle QUIC is advertised or negotiated

check_circle HTTP/3 is advertised or negotiated

HTTP/3 was advertised in the response headers or negotiated for this check. The negotiated protocol was HTTP/3. This check does not measure QUIC connection IDs, packet timing or 0-RTT.

HTTP/3 Server Information

HTTP Version: HTTP/3
Server: cloudflare
Status Code: 301
Response Time: 30.26 ms

Response Headers

Header Value
content-type text/html; charset=UTF-8
date Mon, 02 Nov 2026 17:51:17 GMT
location https://www.cloudflare.com/
strict-transport-security max-age=15780000; includeSubDomains
set-cookie __cf_bm=pqw4_TVMhT_pLGlauNJanJNQ.RwbpR7XR0726QLRN0w-1793641877.6047819-1.0.1.1-GcQcT213gQF9LaNGH2NTu.D4ui7DPaAT4bbsIY6Qh_dSJ.q.A2aMXYeCXUieoy.ubUTUWicbEvU6WeUAbX.EP0tEPkid8WnGSKOvDgHcn7d6RbHXzea1HOKsUQ4ogJDu; HttpOnly; Secure; Path=/; Domain=cloudflare.com; Expires=Mon, 02 Nov 2026 18:21:17 GMT
report-to {"group":"cf-nel","max_age":604800,"endpoints":[{"url":"https://a.nel.cloudflare.com/report/v4?s=W56VaBoTj%2F198xs3ezObEtIc7KfNZCEPi90Cv7%2BOWIgTQEuazjfaS7%2F38fDAIWwie3Y5Ps15IIBzE%2BkVUvCLI%2FMzCrNw%2Fx0Vq8kRCzXqy5HOhnVO3XwzkpazDQHTeJQ2"}]}
nel {"report_to":"cf-nel","success_fraction":0.0,"max_age":604800}
server cloudflare
priority u=3,i=?0
cf-ray a544fc870835dcb4-FRA
alt-svc h3=":443"; ma=86400
server-timing cfExtPri