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About HTTP Security Headers Checker — Free Online Tool
HTTP Security Headers Checker reads the response headers of a URL and grades six of them, from A+ down to F.
Six headers are examined: Strict-Transport-Security, Content-Security-Policy, X-Content-Type-Options, X-Frame-Options, Referrer-Policy and Permissions-Policy. Each is listed with the value the server actually sent and a recommended value you can copy, and the grade is nothing more than how many of the six passed. The test is presence — plus the exact nosniff value for X-Content-Type-Options — and not quality: no policy is parsed, so a Content-Security-Policy of default-src * counts as a pass here while protecting nothing.
The URL goes to ShortTrick's own server, which makes the request and returns the headers; none of it is handed to an external scanning service. Only response headers for the single address you entered are read.
Checking a site before a security review, confirming a header added at the proxy actually reaches the browser, comparing a staging host against production, and finding which header a new deployment dropped.
Also known as: content security policy tester · http headers audit · check security headers · security headers test · test security headers
When to use it
Missing security headers expose your website and visitors to protocol downgrade attacks, malicious iframe embedding, and code injection exploits.
How it works
Probes the target domain via HTTPS and evaluates presence, configuration, and directives of essential security headers.
The Essential Security Headers
Strict-Transport-Security (HSTS), Content-Security-Policy (CSP), X-Content-Type-Options: nosniff, X-Frame-Options: DENY, and Referrer-Policy.
How to Use HTTP Security Headers Checker in 4 Easy Steps
Follow this simple guide to process your files in seconds directly inside your browser tab.
Provide Input for HTTP Security Headers Checker
Paste your payload, code snippet, or string into the HTTP Security Headers Checker editor workspace. Web security auditor that inspects HTTP response headers against OWASP security guidelines to verify protection against clickjacking, XSS, and MIME-sniffing.
Configure Formatting & Validation Rules
Select indentation preferences, minification, encoding options, or validation rules. Missing security headers expose your website and visitors to protocol downgrade attacks, malicious iframe embedding, and code injection exploits.
Run In-Browser Engine
The engine executes HTTP Security Headers Checker locally in your browser with microsecond latency and zero server transmission.
Copy or Download Output
Copy the sanitized, formatted, or generated output directly to your clipboard or download it for your project.
Why Use HTTP Security Headers Checker on ShortTrick
Engineered for maximum speed, strict privacy, and frictionless digital productivity.
Only The URL Leaves
The address you enter is fetched by our server so the response can be read. Your own IP, cookies and headers are not forwarded, and nothing is stored afterwards.
Microsecond Performance
Optimized AST parsers and Web Crypto APIs process large payloads in HTTP Security Headers Checker in milliseconds.
No Paywall or Account
Built for developers to use HTTP Security Headers Checker instantly without sign-up friction or rate limits.
Syntax Validation & Formatting
HTTP Security Headers Checker highlights syntax errors and enforces standard formatting conventions automatically.
Needs A Connection
Reaching the page under test requires the network.
Dark Mode Optimized
High-contrast typography designed for effortless reading during coding sessions.
Frequently Asked Questions About HTTP Security Headers Checker
Common questions regarding HTTP Security Headers Checker, data privacy, file format compatibility, and usage limits.
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