HTTP Header, Redirect & SSL Expiry Checker

Follow a URL's redirects hop by hop and see the response headers the server sends back — plus when its TLS/SSL certificate expires.

Free · no signup · public URLs only

How it works

  1. We follow every redirect

    Each hop is listed with its status code (301, 302, 307, 308), so you can spot redirect chains and loops.

  2. We show the final response headers

    Server, caching, security headers such as Strict-Transport-Security and Content-Security-Policy, cookies, and content type.

  3. We check the certificate

    For https:// URLs, we read the site's TLS certificate and show its expiry date.

Frequently asked questions

What's the difference between a 301 and a 302 redirect?

301 Moved Permanently tells browsers and search engines the move is permanent, so they update to the new URL. 302 Found is temporary. 307 and 308 are the temporary and permanent equivalents that keep the request method unchanged.

Why do redirect chains matter?

Every extra hop adds latency, and long chains can dilute SEO signals or break if one hop changes. Ideally a URL redirects at most once, straight to its final destination.

What happens when an SSL certificate expires?

Browsers show a full-page security warning and most visitors leave. Renew before the expiry date — and monitor the site so you hear about problems quickly.

Which headers should a site send?

Common security headers include Strict-Transport-Security, Content-Security-Policy, X-Content-Type-Options, and Referrer-Policy. Cache-Control controls how long browsers and CDNs keep a copy.

Know when this URL changes or goes down

Site Monitor watches URLs for downtime and content changes and emails you when something happens. Free for 10 URLs — no credit card.

Start watching free → Explore the live demo

Free plan · 10 URLs · hourly checks · 2 AI summaries/mo · no credit card

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