Response headers & TTFB

What this tool checks

An HTTP header check reads the response your server returns before the page even renders — the status code, Time to First Byte (TTFB), and headers like Cache-Control, Strict-Transport-Security and Content-Encoding. These headers decide whether a crawler treats your page as live, fast and trustworthy, so a wrong status can quietly keep a page out of Google's index and out of the AI answer engines that cite it, and a slow TTFB can throttle how often crawlers fetch it.

What it looks at

HTTP status code

The numeric response (200 OK, 301 redirect, 404/410 gone, 5xx error) that tells a crawler whether the page is live; anything other than 200 or a clean 301 risks dropping it from the index.

TTFB (Time to First Byte)

The time from request to the first byte of the server's response; a slow TTFB (over ~800ms) signals a sluggish server and delays crawling and rendering.

Cache-Control

The header that tells browsers and CDNs how long to store the response; correct caching cuts repeat load time and server load without serving stale pages.

Strict-Transport-Security (HSTS)

A header that forces browsers to always use HTTPS for your domain, protecting against protocol-downgrade attacks and confirming the secure-by-default signal search engines expect.

Content-Encoding (compression)

Shows whether the response is compressed with gzip or Brotli; compression shrinks transfer size and speeds up delivery, especially on mobile.

X-Robots-Tag

An indexing directive delivered in the HTTP header (e.g. noindex, nofollow); because it can silently block a page from search and AI engines, it is easy to miss without a header check.

How to use it

1. Paste your URL into the checker and run the request.
2. Review the flagged status code, TTFB and header values against the expected ones.
3. Fix the misconfigured header (or slow server response) at your server or CDN and re-check.

Frequently asked questions