Content-Language header
An HTTP response header that names the language of the content a server returns, such as en or de. CrawlCheck reads it on the homepage and compares it with the page's lang attribute and the language its words are actually written in.
What Content-Language header does not show
It is a declaration by the server; it does not translate anything, and search engines may ignore it in favour of the page text.
Terms this definition uses
Definitions that name Content-Language header
Related terms in HTTP, edge and rendering
The delivery layer between an origin and a client: proxies, caches, redirects, status codes and the headers that decide what a crawler actually received.
HTTP/3 · Alt-Svc · HTTPS DNS record · Link header · content negotiation · Markdown negotiation · Retry-After · Server-Timing · WWW-Authenticate · Allow header · Content-Digest · Origin server · Reverse proxy · CDN · Edge node · WAF · Bot score · TLS handshake · DNS resolution · DNS timeout · Connection timeout · Read timeout · Redirect chain · Redirect loop · 301 redirect · 302 redirect · 307 redirect · 308 redirect · 304 response · 404 response · 410 response · 429 response · 500 response · 502 response · 503 response · 504 response · HEAD request · GET request · Content type · MIME sniffing · Content encoding · Compression · Brotli · ETag · Last-Modified · If-None-Match · Cache hit · Cache miss · Cache key · Vary header · Stale response · Stale-while-revalidate · Edge redirect · Origin bypass · Response parity · Header parity · hreflang · canonical URL · HSTS · HSTS preload list · Content-Security-Policy · CSP nonce · edge cache · cache split · cache-buster · Cache-Control · Age header · render-blocking resource · payload text share · lazy loading · 404 and 410 status codes
Questions about Content-Language header
What is Content-Language header?
An HTTP response header that names the language of the content a server returns, such as en or de. CrawlCheck reads it on the homepage and compares it with the page's lang attribute and the language its words are actually written in.
What does Content-Language header not show or guarantee?
It is a declaration by the server; it does not translate anything, and search engines may ignore it in favour of the page text.
Which area of the glossary does Content-Language header belong to?
HTTP, edge and rendering: The delivery layer between an origin and a client: proxies, caches, redirects, status codes and the headers that decide what a crawler actually received.
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