Help — Enterno.io

How to Use

Standard Mode

• Enter a URL in the URL field — the http:// protocol is optional and will be added automatically.
• Click "Check" — the tool will make a request from the server and return the HTTP response headers.
• Key headers (Content-Type, Server, Cache-Control, etc.) are shown immediately. Others are hidden — expand with the "More headers: N" button.
• Redirect chains are displayed as separate blocks in order — each 301/302 step is visible.
• Enable Show page HTML source to see the source code with syntax highlighting and a "Copy" button.

Advanced Mode

• Method — GET (default), HEAD (headers only, no body), POST (with request body).
• Referer — URL sent in the Referer header. Useful to test site behavior when coming from another domain.
• Headers — additional HTTP headers, one per line: Accept-Language: en.
• POST Body — request body for POST method (query string or JSON).
• Do not follow redirects — the tool will stop at the first 3xx and show the Location header.
• Timeout — maximum response wait time in seconds (1–30, default 15).
• Max redirects — limit redirect chain depth (0–20).

User-Agent

• Leave the field empty — the server default UA will be used.
• Choose a preset from the dropdown: Chrome, Firefox, Safari, Edge, mobile browsers, Googlebot, Bingbot, curl.
• Enter a custom UA manually — useful for checking mobile versions, responsiveness, and site behavior for bots.

WHOIS — Domain Information

• After checking a URL, a WHOIS query is automatically made to the domain registry.
• Brief view: registrar, creation date and expiration date — always visible.
• Full view ("Details" button): registrar URL, update date, DNSSEC, domain status, name servers.
• Raw WHOIS — complete response text from the registry WHOIS server.
• Over 80 domain zones supported: .ru .com .net .org .io .de .uk .fr .co.uk .com.au and more.
• Expiration date is color-coded: green — more than 90 days, yellow — up to 90 days, orange — up to 30 days, red — expired.
• For some zones, registration data is hidden due to GDPR privacy policies — this is normal.

Header Color Coding

• ■ Content — Content-Type, Content-Length, Content-Encoding, Transfer-Encoding
• ■ Cache — Cache-Control, ETag, Expires, Last-Modified, Vary, Age
• ■ Location — redirect address
• ■ Cookie — Set-Cookie, Cookie
• ■ Security — Strict-Transport-Security, Content-Security-Policy, X-Frame-Options, X-Content-Type-Options, X-XSS-Protection
• ■ X-headers — non-standard headers starting with X-
• ■ Server — Server, X-Powered-By, Via