HTTP Header Viewer
View HTTP response headers for any URL.
HTTP response headers reveal caching policies, security settings, server software, redirects, and content types. Utilitoo's HTTP Header Viewer fetches any public URL and displays the full response header table along with status code and final URL after redirects.
Developers debug CORS and cache-control issues, SEO professionals audit redirect chains, and security teams verify HSTS, CSP, and X-Frame-Options headers on production sites.
Enter a URL and click Fetch headers. The tool tries HEAD first and falls back to GET if needed. Headers are sorted alphabetically for easy scanning. Pair with DNS Lookup to verify domain resolution or URL Encoder for encoding issues.
Requests are made server-side to avoid browser CORS restrictions. Private and local network addresses are blocked for safety. Free for developers and ops teams.
HTTP Header Viewer is built for the inspect-edit-copy loop developers repeat dozens of times per day. Because Utilitoo runs in the browser, you avoid context switching to desktop utilities while reviewing logs, configs, or API responses. When output feeds into production systems, validate on a staging copy first.
Common use cases
- View HTTP response headers for any URL - a common daily workflow on Utilitoo.
- Preparing http header viewer results to paste into pull requests, tickets, or team chat.
- Validating http header viewer data from a third-party API before wiring it into your application.
- Teaching or documenting http header viewer workflows without installing desktop software.
- Cross-checking HTTP Header Viewer output against a colleague's result during pair debugging or code review.
Tips & common mistakes
HTTP Header Viewer runs entirely in your browser on Utilitoo, so you can paste sensitive API payloads, configs, or logs without uploading them. Start with a small sample to confirm the output format, then process the full input. If results look wrong, check for trailing commas, wrong encoding, or mixed line endings - common issues when copying from terminals or log viewers. Keep HTTP Header Viewer in a pinned tab during active development - it is faster than CLI one-offs for quick transforms. Use the Related Tools section to chain utilities without returning to the homepage.
Common errors
- Unexpected output from HTTP Header Viewer - double-check input format, character encoding, and whether the source data was truncated when pasted.
- Browser limits - very large inputs may slow or freeze the tab; split the data into smaller chunks if performance degrades.
How to use
- Enter a URL.
- Click Fetch headers.
- Review status and header table.
Frequently Asked Questions
Why use a header viewer instead of browser DevTools?▼
Server-side fetching avoids CORS limits and shows headers for any public URL without opening the site.
Are private URLs allowed?▼
No. Localhost, private IP ranges, and internal hostnames are blocked to prevent abuse.
HEAD or GET request?▼
HEAD is tried first for efficiency. GET is used automatically if the server rejects HEAD.
Do redirects show the final URL?▼
Yes. The response shows the final URL after following redirects.
Is the URL stored?▼
No. Utilitoo does not log fetched URLs.
Related Tools
DNS Lookup
Look up DNS records for any domain.
URL Encoder / Decoder
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User Agent Parser
Parse browser user agent strings.
IP Lookup
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HTTP Status Codes
Searchable reference for common HTTP status codes.
MIME Type Lookup
Look up MIME types by extension or media type.