1. Nguồn
Bắt tay QUIC trực tiếp + Alt-Svc. Kết quả xác định nguồn gốc của bằng chứng.
The HTTP/3 Test attempts a real QUIC connection to the submitted hostname and reads its Alt-Svc discovery signal. The result separates HTTP/3 that is confirmed from HTTP/3 that is only advertised.
Chạy một kiểm tra thực tế ở trên
Gửi một URL công khai, tên miền, hoặc từ khóa. Novaverb sẽ chỉ hiển thị bằng chứng mà công cụ này thực sự có thể lấy hoặc đo lường.
An HTTP/3 test is a check of whether a server answers HTTP/3, the HTTP version carried over QUIC, a UDP-based transport. The Novaverb HTTP/3 Test reads the live HTTPS discovery signal, then attempts a real QUIC handshake and HTTP/3 request, and reports an advertised capability separately from a confirmed one.
The HTTP/3 test checks two signals for the submitted hostname: whether the Alt-Svc header advertises h3, and whether a real QUIC connection offering ALPN h3 completes. A confirmed result also records the QUIC version, whether 0-RTT was accepted, the HTTP status and the timings for first packet, QUIC plus TLS handshake and HTTP/3 response.
The HTTP/3 test is for people who run a site's public edge. An engineer who enabled QUIC at a CDN confirms that the handshake completes. An operator who sees h3 advertised checks whether a firewall blocks UDP 443. A site owner with audiences on unreliable mobile networks checks whether HTTP/3 is reachable at all.
An HTTP/3 test catches the gap between announcing HTTP/3 and delivering it. An Alt-Svc header can point at an endpoint that never answers because UDP 443 is blocked or the QUIC listener is misconfigured. Clients then quietly fall back to HTTP/2, so the failure stays unseen until a real handshake is attempted.
The HTTP/3 test works in a set order. The Alt-Svc header is read first, because that is how an h3 endpoint is discovered. A real HTTP/3 request is then attempted over QUIC. Support is reported as confirmed only when an actual h3 response is received, so advertisement and confirmation stay separate findings throughout.
Enter a domain or any URL on the site into the HTTP/3 test. Only the origin is used, so http or https, www or a full path are all normalized. A private host is refused. HTTP/3 travels over UDP, so a network that blocks QUIC can make a supporting site look unsupported from that vantage point.
yourdomain.comBất kỳ hình thức địa chỉ nào cũng hoạt động. http hoặc https, có hoặc không có www, chỉ tên miền hay một đường dẫn đầy đủ - chúng tôi chuẩn hóa cho bạn.https://www.yourdomain.comHTTP/3 chạy trên QUIC qua UDP 443; chúng tôi phân giải máy chủ gốc và thử kết nối trực tiếp.Reading 'unsupported' as a tool errorNếu UDP 443 bị lọc trên đường dẫn, một yêu cầu h3 thực sự không thể hoàn thành - 'không được hỗ trợ' là phát hiện chính xác, không phải lỗi.The HTTP/3 test report contains a verdict, status chips, discovery facts and an evidence boundary. The verdict reads HTTP/3 is confirmed, HTTP/3 is advertised or HTTP/3 was not confirmed. A confirmed result adds protocol evidence and a QUIC timeline. Server and raw header fingerprints are intentionally omitted from the public result.
Read an HTTP/3 test result by its verdict. Confirmed means a live HTTP/3 handshake over QUIC completed in this test. Advertised means the server announced h3 through Alt-Svc but this probe did not complete a QUIC handshake. Not confirmed means neither was observed. A live handshake is stronger evidence than an advertisement alone.
HTTP/3 truyền HTTP qua QUIC, một giao thức vận chuyển dựa trên UDP. Trình kiểm tra này trước tiên đọc tín hiệu phát hiện HTTPS trực tiếp, sau đó thử một bắt tay QUIC thật và một yêu cầu HTTP/3. Kết quả tách biệt khả năng được công bố với khả năng đã được xác nhận.
Kiểm tra khả năng tiếp cận UDP, chính sách CDN edge, cấu hình chứng chỉ/SNI và xem liệu probe có bị chặn hay không. Chỉ riêng một header Alt-Svc không chứng minh được rằng QUIC có thể hoàn tất.
Một bắt tay QUIC + HTTP/3 thực sự khi được xác nhận, hoặc một tín hiệu phát hiện được gán nhãn rõ ràng khi chỉ có h3 được công bố.
Nó không đo tốc độ trang, Core Web Vitals, mọi điểm edge địa lý, hay việc sử dụng HTTP/3 của tất cả khách truy cập.
"Xác nhận" có nghĩa là một cuộc bắt tay HTTP/3 (QUIC) đã hoàn thành; "Quảng cáo" có nghĩa là h3 đã được thông báo qua Alt-Svc nhưng chưa được xác nhận bởi kiểm tra này.
The HTTP/3 test gets its data from a live QUIC handshake and the Alt-Svc header of a live HTTPS response. Both come from one fresh probe sent by the measurement service to the submitted hostname at the time of the test, so the result describes this HTTPS edge as that probe reached it.
The HTTP/3 test does not tell you that HTTP/3 works on every CDN edge, browser, network or visitor path. One fresh QUIC probe is attempted from the measurement service. The result does not measure page speed or Core Web Vitals, does not show HTTP/3 usage by all visitors and cannot rule out filtering on other networks.
An HTTP/3 test result proves whether a real HTTP/3 request over QUIC succeeded from the probe, not whether HTTP/3 is advertised. A confirmed result proves a completed handshake and an h3 response. An unconfirmed result proves only that this probe did not complete, which can be the network path and not the server.
Bắt tay QUIC trực tiếp + Alt-Svc. Kết quả xác định nguồn gốc của bằng chứng.
Phép kiểm tra thử mở một kết nối QUIC thật với ALPN h3, đồng thời đọc tín hiệu khám phá Alt-Svc. "Đã xác nhận" nghĩa là một lần bắt tay HTTP/3 thật đã hoàn tất; "đã công bố" nghĩa là h3 được thông báo nhưng chưa được xác nhận ở đây.
Sử dụng phát hiện để xác minh một vấn đề, sau đó kết nối một không gian làm việc khi bạn cần lịch sử, giám sát hoặc phân tích toàn bộ trang web.
The HTTP/3 test applies three IETF specifications. RFC 9114 defines HTTP/3. RFC 9000 defines the QUIC transport that HTTP/3 runs on. RFC 7838 defines the Alt-Svc header used for discovery. Keeping discovery apart from confirmation follows directly from RFC 7838, which describes an advertisement and not a guarantee.
Thực hiện trọn vẹn một yêu cầu HTTP/3 thật để xác nhận có hỗ trợ, chứ không chỉ dựa vào lời khai báo.
Đọc thông số kỹ thuậtMở một kết nối QUIC qua UDP như là phương tiện cho HTTP/3.
Đọc thông số kỹ thuậtĐọc tiêu đề Alt-Svc quảng cáo một điểm cuối h3 để khám phá.
Đọc thông số kỹ thuậtVerify an HTTP/3 test result in a browser. Open the developer tools, show the protocol column in the network panel and reload the page, since browsers typically connect over HTTP/2 first, read Alt-Svc and then upgrade on later requests. A request listed as h3 confirms it. Also confirm that firewalls allow inbound UDP on port 443.
A typical HTTP/3 test finding on a site that enabled HTTP/3 at its CDN edge reads HTTP/3 is confirmed, with QUIC v1, an HTTP status and a QUIC timeline. The finding that needs work reads HTTP/3 is advertised: h3 appears in Alt-Svc, the QUIC handshake did not complete, so check UDP reachability first.
The HTTP/3 test is free and needs no account for a live probe. An account is needed when one probe is not the whole question: a workspace tracks HTTP/3 over QUIC, HTTP/2 and TLS support across the whole site over time and saves the evidence, so a later change at the edge is recorded.
A Novaverb workspace adds monitoring and a site-wide crawl to the HTTP/3 test. Site Health continues the job as a source-aware technical checklist that prioritizes supported findings and records fresh rechecks. Results are saved as evidence, and an advertised but unconfirmed finding can be turned into a task that is rechecked.
A free HTTP/3 test is not enough when audiences reach the site through many edges and networks. A single probe from the measurement service cannot show every geographic edge. Each additional hostname needs its own test, an edge policy that changes needs recurring checks, and a speed question needs repeated field or browser measurements.
After running the HTTP/3 test, respond to the verdict. For an advertised result, check UDP reachability, CDN edge policy and certificate and SNI configuration. For a not confirmed result, enable QUIC on the public edge, allow UDP 443 and return an Alt-Svc h3 signal. Then retest. A confirmed result needs no further action.
The HTTP/3 test pairs with free tools that cover the rest of the connection. The HTTP/2 Test reads the ALPN protocol on a TLS connection, the fallback when QUIC fails. The Server Response Time Checker measures Time to First Byte with DNS, TCP and TLS latency. The Website Performance Test compares HTTP response timing from available probe locations.
The HTTP/3 test FAQ answers what HTTP/3 and QUIC are, how confirmed differs from advertised and how clients discover HTTP/3 through Alt-Svc. Other questions cover enabling HTTP/3 on a server, why a site advertises h3 without confirming it, whether HTTP/3 is needed alongside HTTP/2 and whether HTTP/3 requires TLS.
It attempts a real QUIC connection offering ALPN h3 to confirm your server actually speaks HTTP/3, and separately reads the Alt-Svc header to report whether an h3 endpoint is merely advertised.
HTTP/3 is the latest HTTP version, defined in RFC 9114, running over QUIC instead of TCP. QUIC uses UDP, integrates TLS 1.3, and eliminates TCP head-of-line blocking, improving performance on lossy or high-latency networks.
Confirmed means a live HTTP/3 handshake over QUIC actually completed in this test. Advertised means your server announced an h3 option in the Alt-Svc header, but this test did not verify that endpoint responds.
QUIC is a transport protocol over UDP that combines connection setup with TLS 1.3 encryption and supports stream multiplexing without head-of-line blocking. HTTP/3 is HTTP mapped onto QUIC, so confirming HTTP/3 means completing a QUIC handshake.
A server sends an Alt-Svc response header advertising an h3 endpoint, telling clients they may retry over QUIC. Browsers typically connect first over HTTP/2, read Alt-Svc, then upgrade to HTTP/3 on subsequent requests.
Enable QUIC and HTTP/3 in your web server or CDN, allow inbound UDP on port 443 through firewalls, and emit an Alt-Svc header advertising h3. Many sites get HTTP/3 simply by enabling it at their CDN edge.
Often UDP 443 is blocked by a firewall, the QUIC listener is misconfigured, or only the edge speaks h3 intermittently. Advertising via Alt-Svc is a promise; a failed QUIC handshake means clients quietly fall back to HTTP/2.
Not strictly. HTTP/3 mainly helps users on unreliable or high-latency mobile networks by surviving packet loss and network changes better than TCP. It is a worthwhile enhancement rather than a replacement for a working HTTP/2 setup.
Yes. QUIC integrates TLS 1.3 directly into the transport, so HTTP/3 is always encrypted by design. There is no cleartext HTTP/3, and a valid certificate is required for the handshake this test performs.
It can reduce connection setup cost or recover better on some networks, but a successful handshake does not prove a faster page. Confirm the effect with repeated field or browser measurements for the audiences you serve.