HTTP Header Diff Checker

Comparing HTTP Headers Before and After Website Changes

HTTP headers often change when a site moves hosting, adds a CDN, updates server configuration, changes cache rules, enables security headers, or modifies redirects. Small header changes can affect caching, security, SEO, API behavior, and browser handling.

This HTTP Header Diff Checker helps you compare two sets of response headers, find added headers, removed headers, changed values, and unchanged values directly in your browser.

Reviewing Response Header Changes in the Browser

1. Paste the first set of HTTP headers into the before box.
2. Paste the second set of HTTP headers into the after box.
3. Click Compare Headers.
4. Review added, removed, changed, and unchanged header values.

Common HTTP Header Diff Use Cases

• Comparing headers before and after a CDN or Cloudflare change.
• Checking cache-control changes after deployment.
• Reviewing security header changes such as CSP, HSTS, and X-Frame-Options.
• Comparing API response headers across environments.
• Finding removed headers after server or proxy configuration updates.

Example Header Comparison

HTTP/1.1 200 OK
Content-Type: text/html; charset=utf-8
Cache-Control: no-cache
X-Frame-Options: SAMEORIGIN
X-Content-Type-Options: nosniff
Server: nginx

HTTP/1.1 200 OK
Content-Type: text/html; charset=utf-8
Cache-Control: public, max-age=3600
Strict-Transport-Security: max-age=31536000; includeSubDomains
X-Content-Type-Options: nosniff
Content-Security-Policy: default-src 'self';
Server: cloudflare

Frequently Asked Questions

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