HTTP Header Checker
View every HTTP response header a URL returns, with explanations for the security-relevant ones.
Response headers control caching, security, tracking and how a browser trusts your site — but most are invisible unless you crack open devtools. This checker lists every header your server returns, in the order it returns them, and calls out the security-relevant ones with plain-English guidance on what each does.
HTTP Header Checker evaluates the following signals from your target host:
Frequently asked questions
- It shows headers for the final destination and lists every hop.
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