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HTTP API · Free

HTTP Header Checker
API

Fetch a URL and return its response headers + a security grade based on HSTS, CSP, X-Content-Type-Options, X-Frame-Options, Referrer-Policy, and Permissions-Policy presence.

Read the docsTry the visual tool

Free. No API key. CORS-enabled. Rate-limited per IP.

GEThttps://api.domainee.dev/v1/tools/http-header-checker?url=https%3A%2F%2Fdomainee.dev

Fetch a URL and return its response headers + a security grade based on HSTS, CSP, X-Content-Type-Options, X-Frame-Options, Referrer-Policy, and Permissions-Policy presence.

Free. No API key required. CORS-enabled. Rate-limited per IP at 30/min and 500/day.

Parameters

NameInTypeDescription
urlrequiredquerystring
Full URL to fetch (must include scheme).
example: https://domainee.dev

Example request

curl
curl -s "https://api.domainee.dev/v1/tools/http-header-checker?url=https://domainee.dev" | jq

Example response

response.json
{
  "ok": true,
  "data": {
    "url": "https://domainee.dev",
    "status": 200,
    "statusText": "OK",
    "headers": {
      "server": "Caddy",
      "content-type": "text/html"
    },
    "securityHeaders": [
      {
        "name": "strict-transport-security",
        "present": true
      },
      {
        "name": "content-security-policy",
        "present": false
      }
    ],
    "grade": "B"
  }
}

Other languages

fetch.js
const res = await fetch("https://api.domainee.dev/v1/tools/http-header-checker?url=https%3A%2F%2Fdomainee.dev");
const { ok, data } = await res.json();
requests.py
import requests
r = requests.get(
    "https://api.domainee.dev/v1/tools/http-header-checker",
    params={"url":"https://domainee.dev"},
)
data = r.json()["data"]

Rate limits & errors

  • 30 requests/minute and 500 requests/day per IP. Exceeding either returns HTTP 429 with a Retry-After header.
  • All responses are JSON with the envelope { "ok": true, "data": {...} } on success or { "ok": false, "error": { "code", "message" } } on failure.
  • code values are stable; safe to switch on programmatically. message is human-friendly and may change.
Prefer a UI?

Try the http header checker in your browser →

No code, no curl. Type a domain, get a result.

Full reference

Documentation for /v1/tools/http-header-checker →

All parameters, error codes, edge cases.

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