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SSL API · Free

SSL Certificate Checker
API

Returns TLS certificate details for any public hostname: subject, issuer, validity, alt names, cipher, full chain.

Read the docsTry the visual tool

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

GEThttps://api.domainee.dev/v1/tools/ssl-check?host=domainee.dev

Returns TLS certificate details for any public hostname: subject, issuer, validity, alt names, cipher, full chain.

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

Parameters

NameInTypeDescription
hostrequiredquerystring
Hostname to check. Optionally with `:port` (default 443).
example: domainee.dev

Example request

curl
curl -s "https://api.domainee.dev/v1/tools/ssl-check?host=domainee.dev" | jq

Example response

response.json
{
  "ok": true,
  "data": {
    "host": "domainee.dev",
    "port": 443,
    "protocol": "TLSv1.3",
    "cipher": {
      "name": "TLS_AES_256_GCM_SHA384",
      "version": "TLSv1.3"
    },
    "authorized": true,
    "expired": false,
    "daysUntilExpiry": 71,
    "subject": {
      "CN": "domainee.dev"
    },
    "issuer": {
      "C": "US",
      "O": "Let's Encrypt",
      "CN": "E7"
    },
    "validFrom": "2026-03-15T08:32:14.000Z",
    "validTo": "2026-06-13T08:32:13.000Z",
    "altNames": [
      "domainee.dev",
      "*.domainee.dev"
    ]
  }
}

Other languages

fetch.js
const res = await fetch("https://api.domainee.dev/v1/tools/ssl-check?host=domainee.dev");
const { ok, data } = await res.json();
requests.py
import requests
r = requests.get(
    "https://api.domainee.dev/v1/tools/ssl-check",
    params={"host":"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 ssl certificate checker in your browser →

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

Full reference

Documentation for /v1/tools/ssl-check →

All parameters, error codes, edge cases.

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