host.tools

Security headers grader

HTTP /api/v1/http/security-headers

A+ to F grade for HSTS, CSP, X-Frame-Options, COOP, Referrer-Policy and more.

A
86% — A
URL: https://accounts.google.com/v3/signin/identifier?opparams=%253Fcred_ref%253Dtrue%2526hd%253Dgoogle.com&dsh=S185846142%3A1778323486440068&client_id=761377308534.apps.googleusercontent.com&hd=google.com&o2v=1&redirect_uri=https%3A%2F%2Flogin.corp.google.com%2Foauth&response_type=code&scope=openid+email&service=lso&state=s%3Dm.gutsdev.corp.google.com%3A443%2Fuberproxy%2F%26c%3D1%26d%3Dhttps%3A%2F%2Fm.gutsdev.corp.google.com%2F%3Fupxsrf%253DAM2vRLnCRrP-s_wyShTNo6AeCd06vzfiXcRKfyulLzDoLU3kzg%3A1778323486343%26keyIds%3D588916238%2C1331854303%2C-337386367%2C788849210%2C-1430978537%2C1163017845%2C-100563820%2C2023603197%26maxAge%3D1200%26authLevel%3D1500%26ssoformat%3DCORP_SSO%26x%3DABKNxoz21a-UyTNJCqsXtYrtQBwIxzYv9yu7X0rxe0rqqKUbOQ%3A1778323486400&flowName=GeneralOAuthLite&continue=https%3A%2F%2Faccounts.google.com%2Fsignin%2Foauth%2Flegacy%2Fconsent%3Fauthuser%3Dunknown%26part%3DAJi8hAOOdTgDI3u8VOzpwP3mCSrJCzBtVGES8uANdV31KGOfb_Xh_3iKJELdbMCW9t4v8NvK2PGh_LUkRASbAnVgHPyizF3VeJkiLVbJUupIdHySvCCUIcXyN2kwNSH1H_xYHopNmLKkQHO2vXm1yPoDN0ZKnH-iJ2nUlXdz5wN1u5j8vhw6mi9SYQBb8t9dFCV_AWFMxVqdByWf7QNFcbGavLHG8VfQnFIlrjrt6bUKtMLsumUTMnX59bkV6n8Hi-kfV2YXhvsDwK8OgrbI4k7N-s2BfTxFpTQAiH9pdEyrD9awqYveiQ9ax1u5sQHJB5FQkaJSej6ctZSsFTQMv6bw5YavZWA_0KmonO3VW-15zEthgkPc8MtVJcYuPfPHxD-qhGMeJ1UDvrw-po5J8AENYhO3FGMoYYZL38rPiwsyXgfT-2-TVLU%26flowName%3DGeneralOAuthFlow%26as%3DS185846142%253A1778323486440068%26client_id%3D761377308534.apps.googleusercontent.com%23&app_domain=https%3A%2F%2Flogin.corp.google.com&rart=ANgoxcdSXnnj6Zb5YMk6Yq8MSAh1-JNBg8oMmGszNQbcRf87tRzSp6Zb2bMVIhXximlbRXgDxnTMe9R-xQoCTcKBjxWez0lSLPtaaozz9Y3Rjy4tEvH5XFw
Status 200 · 10 checks
Strict-Transport-Security
max-age=31536000; includeSubDomains
+20
Content-Security-Policy
present
+25
X-Content-Type-Options
should be `nosniff`
+10
X-Frame-Options / frame-ancestors
prevents clickjacking
+10
Referrer-Policy
controls Referer leakage
+8
Permissions-Policy
restricts powerful features
+8
Cross-Origin-Opener-Policy
COOP isolates browsing context
+6
Cross-Origin-Resource-Policy
CORP blocks cross-origin reads
+6
Server header masked
don't leak version
+4
X-Powered-By absent
don't advertise stack
+3
How to use Security headers grader
  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/security-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/security-headers?q=https%3A%2F%2Fm.gutsdev.corp.google.com
curl -s '/api/v1/http/security-headers?q=https%3A%2F%2Fm.gutsdev.corp.google.com'
Embed this tool
<iframe src="/http/security-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 · Security headers grader

Common questions

Is Security headers grader free?
Yes — every tool is free on the web with a 200/hour rate limit per IP. The matching API endpoint /api/v1/http/security-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 security-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 Security headers grader 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.

  • 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