1. Nguồn
Thương lượng TLS ALPN trực tiếp. Kết quả xác định nguồn gốc của bằng chứng.
The HTTP/2 Test opens one live TLS connection to the submitted hostname and reads the protocol selected through ALPN. HTTP/2 is confirmed only when the server negotiates h2.
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/2 test is a check of whether a server speaks HTTP/2 on a real connection. The Novaverb HTTP/2 Test opens one live HTTPS connection, offers h2 and http/1.1 through TLS ALPN and reports the protocol the endpoint selected, which makes the verdict protocol evidence and not a guessed score or a browser simulation.
The HTTP/2 test checks whether ALPN completed and whether h2 was selected for the submitted hostname. Alongside that verdict it records the selected protocol, the TLS version, the HTTP status code and the timings for TCP connect, TLS plus ALPN and the HTTPS response. The Alt-Svc header is read to note an HTTP/3 advertisement.
The HTTP/2 test is for people who configure or audit how a site is delivered. A developer confirms that enabling h2 on the TLS listener took effect. A site owner behind a CDN checks what visitors negotiate at the public hostname. A technical SEO records the delivery protocol as part of a performance review.
An HTTP/2 test catches a site that quietly falls back to HTTP/1.1. A header can claim HTTP/2 while the layer that terminates TLS, often a CDN or reverse proxy, never negotiates it. HTTP/2 multiplexes many requests over one connection, so a missed negotiation leaves resource-heavy pages with the request overhead of HTTP/1.1.
The HTTP/2 test works in a short sequence. The input is normalized to the site's origin and a live TLS handshake is completed. The ALPN-negotiated protocol is read, and HTTP/2 is confirmed only when the server actually negotiates h2. The Alt-Svc response header is then read separately to note whether HTTP/3 is advertised.
Enter a domain or any URL on the site into the HTTP/2 test. Only the origin matters, so the path and query are normalized away before the handshake and the secure origin is tested either way. The exact hostname submitted is the one probed. A search phrase is not an address, and a private host is refused.
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. Dù bạn nhập cách nào, chúng tôi vẫn kiểm tra máy chủ gốc an toàn.https://www.yourdomain.com/pageMột URL đầy đủ kèm đường dẫn cũng được - HTTP/2 là thuộc tính của kết nối, nên chúng tôi kiểm tra máy chủ gốc đứng sau nó.fast web hostingĐó là một cụm từ tìm kiếm, không phải là địa chỉ - hãy nhập tên miền hoặc URL để kiểm tra.The HTTP/2 test report contains a verdict, protocol evidence, a connection timeline and endpoint facts. The verdict reads HTTP/2 is supported or HTTP/2 was not negotiated. Protocol evidence shows h2, ALPN, the selected protocol and the TLS version. The timeline gives timings in milliseconds, and endpoint facts add the status code and the HTTP/3 signal.
Read an HTTP/2 test result from the verdict down. Supported means the TLS handshake selected h2 for this HTTPS endpoint. Not negotiated means the endpoint did not select h2, and a compatible client can fall back to HTTP/1.1. An HTTP/3 signal marked advertised is an Alt-Svc observation only, not a QUIC handshake.
Trình kiểm tra này mở một kết nối HTTPS thật, chào h2 và http/1.1 qua TLS ALPN, rồi báo cáo giao thức mà điểm cuối chọn. Nhờ vậy kết luận là bằng chứng về giao thức - không phải một điểm số phỏng đoán hay một mô phỏng trình duyệt.
Kiểm tra chứng chỉ và hostname SNI, chính sách TLS của CDN hoặc bộ cân bằng tải, hỗ trợ ALPN trong ngăn xếp TLS, và liệu có proxy nào đang kết thúc kết nối trước khi nó đến máy chủ gốc của bạn hay không.
Giao thức ALPN đã chọn trên một kết nối TLS mới, cộng với thời gian kết nối cơ bản và trạng thái HTTP.
Nó không đảm bảo trang nhanh hơn, khả năng HTTP/3, hỗ trợ trình duyệt trên mọi mạng, hoặc Core Web Vitals tốt.
Phép kiểm tra này thực hiện một lượt bắt tay TLS thật và đọc giao thức được thương lượng qua ALPN; khả năng hỗ trợ HTTP/3 được suy ra từ header Alt-Svc, không phải từ một lượt bắt tay QUIC.
The HTTP/2 test gets its data from live TLS ALPN negotiation: one fresh TLS connection from the measurement service to the submitted hostname. The protocol is read from the handshake itself and not from a header that claims support. A CDN in front of the origin answers the check, as it does for visitors.
The HTTP/2 test does not tell you about protocol support on every edge or network path. One live TLS handshake proves the protocol negotiated by this probe. The result does not measure page speed, subresources or Core Web Vitals, does not cover every CDN location and does not confirm that HTTP/3 works.
An HTTP/2 test result proves the ALPN protocol selected on one fresh TLS connection, plus basic connection timing and the HTTP status. Negotiating h2 shows that a connection is multiplexed, not that a page is fast. When the handshake cannot be completed, the test says so and does not claim that HTTP/2 is absent.
Thương lượng TLS ALPN trực tiếp. Kết quả xác định nguồn gốc của bằng chứng.
Kiểm tra này thực hiện một lần bắt tay TLS trực tiếp tới tên máy chủ đã gửi. Nó chứng minh giao thức được thương lượng trong lần thăm dò này, chứ không chứng minh mức hỗ trợ giao thức trên mọi máy chủ biên hay mọi đường mạng.
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/2 test applies two IETF specifications. RFC 9113 defines HTTP/2 itself. RFC 7301 defines Application-Layer Protocol Negotiation, the TLS extension the test reads to learn which protocol was actually agreed. Reading ALPN and not a response header is what makes the answer a measurement instead of a claim.
Xác nhận hỗ trợ HTTP/2 theo đúng cách giao thức yêu cầu: qua ALPN, chứ không phải qua một khai báo trong header.
Đọc thông số kỹ thuậtĐọc giao thức đã thương lượng ALPN trong quá trình bắt tay TLS trực tiếp.
Đọc thông số kỹ thuậtVerify an HTTP/2 test result in a browser. Open the developer tools, load the page with the network panel open and show the protocol column, where a request served over HTTP/2 is listed as h2. Check the public hostname visitors use, because a CDN can negotiate HTTP/2 while the origin uses a different protocol.
A typical HTTP/2 test finding reads HTTP/2 is supported, with ALPN negotiated, h2 as the selected protocol, the TLS version shown and the HTTP/3 signal marked advertised. The contrasting finding reads HTTP/2 was not negotiated with http/1.1 as the selected protocol, which points at the CDN, load balancer or proxy that terminates TLS.
The HTTP/2 test is free and runs with no account. Each run is one live handshake for one hostname. An account is needed to go further than a single probe: a workspace tracks HTTP/2, HTTP/3 and TLS support across the whole site over time and keeps each result as saved evidence.
A Novaverb workspace adds a whole-site view and a record over time to the HTTP/2 test. Site Health is the product that continues the job: a source-aware technical checklist that prioritizes supported findings and records fresh rechecks. A protocol finding can be moved into a task and rechecked once the configuration changes.
A free HTTP/2 test is not enough when a site is served from several hostnames or CDN locations. One probe describes one HTTPS edge at one moment. Each additional hostname needs its own check, a configuration that changes needs recurring measurement, and any question about speed needs field or browser measurements instead.
After running the HTTP/2 test, a not negotiated result leads to a short list of actions. Confirm HTTPS with a valid certificate on the public endpoint. Enable h2 on the TLS listener of the web server or CDN and keep HTTP/1.1 as a fallback. Then retest the public hostname. A supported result needs no change.
The HTTP/2 test pairs with free tools that measure what a protocol check does not. The HTTP/3 Test attempts a real QUIC handshake, which this test only infers from Alt-Svc. The Server Response Time Checker measures Time to First Byte with DNS, TCP and TLS latency. The Core Web Vitals Checker shows real-user LCP, INP and CLS data.
The HTTP/2 test FAQ answers what HTTP/2 is, how browser and server negotiate it and how to enable it on a site. Other questions compare HTTP/1.1 with HTTP/2, explain why HTTP/2 requires HTTPS in browsers, cover which TLS version a server should use and ask whether HTTP/2 makes a page faster.
It performs a live TLS handshake and reads the ALPN-negotiated protocol to confirm whether your server actually serves HTTP/2. It also reports the TLS version and whether HTTP/3 is advertised via the Alt-Svc header.
HTTP/2 is a major revision of HTTP that multiplexes many requests over a single connection, adds header compression (HPACK), and enables prioritization. It reduces round-trip overhead versus HTTP/1.1, speeding delivery of pages with many resources.
Over HTTPS, HTTP/2 is negotiated during the TLS handshake using ALPN (Application-Layer Protocol Negotiation). The client offers h2, and if the server agrees, the connection uses HTTP/2. This test reads exactly that ALPN result.
Enable the HTTP/2 module in your web server or CDN (for example the http2 directive in modern server builds) and ensure HTTPS with ALPN is active. HTTP/2 in browsers effectively requires TLS, so a valid certificate is prerequisite.
HTTP/1.1 sends requests largely one-at-a-time per connection and can suffer head-of-line blocking. HTTP/2 multiplexes concurrent streams over one connection and compresses headers, cutting latency for resource-heavy pages without opening many parallel connections.
No. HTTP/3 here is only inferred from the Alt-Svc response header, which advertises an h3 endpoint. This ALPN-based test confirms HTTP/2 directly but does not perform a QUIC handshake to prove HTTP/3 works.
The specification allows cleartext HTTP/2, but every major browser only supports it over TLS via ALPN. In practice you need a valid certificate and HTTPS for browsers to negotiate and use HTTP/2 at all.
TLS 1.3 is preferred for its faster handshake and stronger defaults, with TLS 1.2 as an acceptable minimum. HTTP/2's blocklist forbids obsolete ciphers, so modern TLS configuration avoids fallback to HTTP/1.1.
Confirm HTTPS with ALPN is enabled and the HTTP/2 module is on at whichever layer terminates TLS, often a CDN or reverse proxy rather than your origin. Some hosts serve HTTP/2 only at the edge.
It can reduce request overhead when a page loads many resources, but this protocol check does not measure page rendering or real-user speed. Compare field and browser measurements before attributing a speed change to HTTP/2.