Protocol audit

adidas.nl HTTP/2 test

SEO page with a cached HTTP/2, ALPN and TLS negotiation check.

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HTTP/2 / ALPN result

Negotiation result

HTTP/2 was not negotiated

The TLS handshake completed without h2, so this endpoint is currently falling back to HTTP/1.1.

Check the server or CDN TLS/ALPN configuration and make sure h2 is enabled on HTTPS.

Not supported

Protocol: Protocol: none
TLS: TLS: TLS 1.2
Cipher: Cipher: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256

HTTP/2 support

Not supported

Negotiated protocol

none

TLS version

TLS 1.2

Cipher

TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256

Remote IP

87.237.217.231

Checked host

adidas.nl

Port

443

Warnings

server did not negotiate HTTP/2 over ALPN

Tool switcher

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Guides

Practical guides for common HTTP/2 Tester tasks — DNS records, troubleshooting steps, and links to our free tools.

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HTTP/2 Detection Guide for Production Sites
How to confirm HTTP/2 support, read protocol results, and avoid false positives from cached or proxied checks.
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ALPN and HTTP/2 Negotiation Explained
Why ALPN decides whether clients use h2, and how to troubleshoot missing protocol negotiation.
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Common CDN, reverse proxy, and load balancer reasons that HTTP/2 works at one layer but fails at another.
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Browser and Server HTTP/2 Mismatch: How to Debug
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Nginx, Apache, and Caddy HTTP/2 Config Checks
Configuration checkpoints for enabling HTTP/2 safely on common web servers.
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HTTP/2 SEO and Performance Impact
How HTTP/2 support affects crawl efficiency, user experience, and page speed diagnostics.
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Back to HTTP/2 Tester

HTTP/2 / ALPN result

HTTP/2 was not negotiated

Continue with another check

Related articles

HTTP/2 Detection Guide for Production Sites

ALPN and HTTP/2 Negotiation Explained

HTTP/2 TLS Requirements Checklist

h2 vs HTTP/1.1: What the Tester Result Means

HTTP/2 CDN and Proxy Issues to Check First

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Nginx, Apache, and Caddy HTTP/2 Config Checks

HTTP/2 SEO and Performance Impact