host.tools

HTTP headers

HTTP /api/v1/http/headers

Capture every response header, follow redirects, time each hop.

Try: https://host.com https://checkhost.com https://hostinfo.com https://crypt.tools
Related: DNS lookup (dig) DNS propagation Domain WHOIS SSL certificate inspector HTTP headers Security headers grader MX lookup SPF tester DMARC tester
https://accounts.google.com/v3/signin/identifier?continue=https%3A%2F%2Fmail.google.com%2Fmail%2Fu%2F0%2F&dsh=S2047512117%3A1778335728681681&emr=1&followup=https%3A%2F%2Fmail.google.com%2Fmail%2Fu%2F0%2F&osid=1&passive=1209600&service=mail&flowName=WebLiteSignIn&flowEntry=ServiceLogin&ifkv=AWa2Pavtu5ig0cQs2Zvat4HECbfHNxkZkGK34k5mdHrzMOovL1kKpxFDhnvBGVVAEFYKPT7pOhAxpg 200 6 hops 443 ms
Redirect chain
  1. 301 https://mail.google.com 29 ms
  2. 301 https://mail.google.com/mail/ 28 ms
  3. 302 https://mail.google.com/mail/u/0/ 56 ms
  4. 302 https://accounts.google.com/ServiceLogin?service=mail&passive=1209600&osid=1&continue=https://mail.google.com/mail/u/0/&followup=https://mail.google.com/mail/u/0/&emr=1 29 ms
  5. 302 https://accounts.google.com/InteractiveLogin?continue=https://mail.google.com/mail/u/0/&emr=1&followup=https://mail.google.com/mail/u/0/&osid=1&passive=1209600&service=mail&dsh=S2047512117:1778335728681681 42 ms
  6. 200 https://accounts.google.com/v3/signin/identifier?continue=https%3A%2F%2Fmail.google.com%2Fmail%2Fu%2F0%2F&dsh=S2047512117%3A1778335728681681&emr=1&followup=https%3A%2F%2Fmail.google.com%2Fmail%2Fu%2F0%2F&osid=1&passive=1209600&service=mail&flowName=WebLiteSignIn&flowEntry=ServiceLogin&ifkv=AWa2Pavtu5ig0cQs2Zvat4HECbfHNxkZkGK34k5mdHrzMOovL1kKpxFDhnvBGVVAEFYKPT7pOhAxpg 135 ms
Final response headers (24)
content-type text/html; charset=utf-8
x-frame-options DENY
set-cookie __Host-GAPS=1:eKrPmkRrPEKKlEmjDLxljNYQmc0TIQ:tZqFx1XZGXd-WCkQ; Expires=Mon, 08-May-2028 14:08:48 GMT; Path=/; Secure; HttpOnly; Priority=HIGH
vary Sec-Fetch-Dest, Sec-Fetch-Mode, Sec-Fetch-Site
x-auto-login realm=com.google&args=service%3Dmail%26continue%3Dhttps://mail.google.com/mail/u/0/
link <https://workspace.google.com/gmail/>; rel="canonical"
x-ua-compatible IE=edge
cache-control no-cache, no-store, max-age=0, must-revalidate
pragma no-cache
expires Mon, 01 Jan 1990 00:00:00 GMT
date Sat, 09 May 2026 14:08:48 GMT
strict-transport-security max-age=31536000; includeSubDomains
report-to {"group":"AccountsSignInUi","max_age":2592000,"endpoints":[{"url":"https://csp.withgoogle.com/csp/report-to/AccountsSignInUi"}]}
accept-ch Sec-CH-UA-Arch, Sec-CH-UA-Bitness, Sec-CH-UA-Full-Version, Sec-CH-UA-Full-Version-List, Sec-CH-UA-Model, Sec-CH-UA-WoW64, Sec-CH-UA-Form-Factors, Sec-CH-UA-Platform, Sec-CH-UA-Platform-Version
cross-origin-opener-policy-report-only same-origin; report-to="AccountsSignInUi"
content-security-policy require-trusted-types-for 'script';report-uri /v3/signin/_/AccountsSignInUi/cspreport, script-src 'report-sample' 'nonce-IlV_n5o1Mm2NPCjBTGJX0g' 'unsafe-inline';object-src 'none';base-uri 'self';report-uri /v3/signin/_/AccountsSignInUi/cspreport;worker-src 'self'
permissions-policy ch-ua-arch=*, ch-ua-bitness=*, ch-ua-full-version=*, ch-ua-full-version-list=*, ch-ua-model=*, ch-ua-wow64=*, ch-ua-form-factors=*, ch-ua-platform=*, ch-ua-platform-version=*
cross-origin-resource-policy same-site
reporting-endpoints default="/v3/signin/_/AccountsSignInUi/web-reports?context=eJwNw11IU3EcBuAx_b2ECYkfJbuIGEQtmJ0GrqAihoSYZ9tZ_0kR5HRs4iJ27Owo9HHR90VQoLAJu4oIKqOCqIwuqouiJMrURSfTrvoSiyxKuljY-8BTNVOxocrjal_vcT30PnCH9n907-RC9Zy7yGfevZI825fG5TSf4yJvH3ktIe7tmpCDvGnNpITYLE5KjvU9U2LwYH1J8mw1luQk-7aUxM_Ji2-kh5_4HHnOv444UnvUkZZFR1p55fR78fBYaUZesmvdrFTyjuFZaeHy8Ta4TrTha2s7vvEdv477fGVKx9BnHQX2NYXh532ZMDp5MRcG7DDmz0bwg6_nI7jFmwej2Mo370Vxmyu_R-GJGVjNa9nHAQ5y1wEDKb52ysANnuYPnB01YPHTtwbG-FnZwAu-fCGGq2w-iiHHK-7uRh0vNCj85ppGhXoe8ioU-GdQ4Q_v2qYQ4ZEOhU_dCnP8l8tcl1RYxV_-KczzwJJCXyIOm81jcejDccSXd2Av11YvW1gqj6PGeXx-tMK7MWkeSmRS6aydsQ_3WGbWTmdT3f12b38ml7YG0lYioAWCWrPW3KRpiT7tP7Y6xtY"
content-encoding gzip
server ESF
x-xss-protection 0
x-content-type-options nosniff
alt-svc h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
Tech stack
HTTP/3 (QUIC)
How to use HTTP headers
  1. 1
    Paste your input

    Enter the value at the top — domain, IP, URL, email, ASN, hash, whatever fits this tool. The smart input auto-detects type.

  2. 2
    Click "Inspect"

    host.tools issues real probes (DNS, HTTP, TCP, TLS, WHOIS where applicable) and renders the result in milliseconds.

  3. 3
    Open the API tab

    Every web tool has a sibling /api/v1/http/headers JSON endpoint with the same payload. One copy-as-curl click and you're scripting it.

Why this matters

Headers are how the modern web declares its security posture. Auditing them is the highest-ROI thing you can do this week.

API equivalent
/api/v1/http/headers?q=mail.google.com 
curl -s '/api/v1/http/headers?q=mail.google.com'
Embed this tool
<iframe src="/http/headers?q={INPUT}&embed=1"
  width="100%" height="600" frameborder="0"></iframe>

Drop into any HTML page. The embed=1 flag hides nav and footer.

FAQ · HTTP headers

Common questions

Is HTTP headers free?
Yes — every tool is free on the web with a 200/hour rate limit per IP. The matching API endpoint /api/v1/http/headers is free up to 100 requests/hour, no key required.
Where does the data come from?
Real-time probes against authoritative sources (DNS root, RIRs, registries, the target server itself), plus partner data feeds from hostinfo.com (GeoIP/ASN) and hostcheck.com (reputation).
How fresh are the results?
Live by default. Cached for 5 minutes to make repeat queries instant; pass ?nocache=1 for a forced refresh.
Can I run this from the command line?
Yes — every tool ships with a copy-as-curl. There's also an official CLI: host.tools http headers YOUR_INPUT.
Can I monitor results over time?
Pro tier lets you schedule any tool to run every 1/5/15/60 min and alert on diff. See monitors.
host.tools Pro

Run HTTP headers on a schedule. Get pinged when it changes.

Pro gets you bulk lookups, monitors, webhook alerts, history, exports and 10,000 API calls/day. $19/mo.

See pricing Tour monitors
  • ✓Schedule any tool — every 1, 5, 15, 60 min
  • ✓Diff against last run, alert on change
  • ✓Webhook + email + Slack + PagerDuty + OpsGenie
  • ✓Bulk CSV upload, 1,000 inputs per job
  • ✓Export results as CSV / NDJSON / Excel
  • ✓90-day history, comparison view