Content-Language HTTP header missing: what it is, why it matters, and how to fix it
The server does not send a Content-Language HTTP header indicating the language of the page. While not critical, this header provides an additional language signal to search engines and browsers.
Where this fits: indexability in SEO
Why content-language http header missing hurts your rankings
The Content-Language header is a supplementary signal that helps browsers and search engines determine the page language. While Google primarily relies on the page content itself to detect language, providing consistent language signals across all channels (HTML lang, hreflang, Content-Language header) strengthens language targeting.
This is an advisory finding: not a defect, but an opportunity flagged so you can decide deliberately rather than by accident.
How to fix it
Add the Content-Language HTTP header to your server responses, matching the language of the page content. This can be configured in your web server, CMS, or application layer.
# Nginx configuration
add_header Content-Language en;Frequently asked questions
What does "Content-Language HTTP header missing" mean?
The server does not send a Content-Language HTTP header indicating the language of the page. While not critical, this header provides an additional language signal to search engines and browsers.
Why does content-language http header missing matter for SEO?
The Content-Language header is a supplementary signal that helps browsers and search engines determine the page language. While Google primarily relies on the page content itself to detect language, providing consistent language signals across all channels (HTML lang, hreflang, Content-Language header) strengthens language targeting.
How do I fix content-language http header missing?
Add the Content-Language HTTP header to your server responses, matching the language of the page content. This can be configured in your web server, CMS, or application layer.
How serious is this issue?
This is an advisory finding: not a defect, but an opportunity flagged so you can decide deliberately rather than by accident. It belongs to the indexability family of checks.
How do I find every page affected by this on my site?
Run a free Dr Urls audit: it crawls your site, detects content-language http header missing on every affected page, shows example URLs, and generates a ready-to-use fix task. Re-scan after fixing to verify the issue is gone.
Does your site have this issue?
A free Dr Urls audit crawls your site, finds every page affected by content-language http header missing, and hands you a ready-made fix task.
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