HTTP Compare
Fetch two URLs in parallel and diff response headers, status codes and timings — production vs staging, before vs after, A/B environments.
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Why compare HTTP responses?
Most production incidents trace to a header that changed silently — Cache-Control flipping from public to private after a deploy, a CSP directive narrower in staging than prod, an X-Frame-Options that disappeared along with the security middleware. The HTTP Compare tool fetches two URLs simultaneously and lays the responses side-by-side: same status code, same headers, same timing breakdown — or, more usefully, exactly which lines differ.
Frequently Asked Questions
Are both URLs fetched in parallel?
Yes — concurrent fetches with the same timeout, so the timing column reflects real latency rather than serial-fetch noise.
Which headers are compared?
Every response header on either side. Identical values are dimmed; differing values are highlighted; one-side-only headers stand out.
Does this follow redirects?
Yes — the final response is what gets compared. Use /redirects to inspect each hop of the chain.
Is the request body included?
Not by default — only headers + status + timing. Body diff would require sanitisation; out of scope for this tool.