DEVELOPER REST API V1
Free SSL Certificate & Security API
Integrate real-time SSL/TLS certificate health, expiration countdowns, DNS CAA policy checks, and HSTS scores into your apps, CI/CD pipelines, and monitoring tools.
100% Free Forever Universal CORS (Access-Control-Allow-Origin: *) No API Keys Required 📥 OpenAPI 3.1 JSON
Interactive API Playground GET /api/v1/check
Test API Request
Execute a live request directly against the global edge network.
// Click "Send" above to execute live API test... Code Snippets 6+ Languages
Integration Code
Ready-to-use copy-paste snippets for your apps and CI/CD pipelines.
cURL CLI
curl -s "https://checksslexpiry.com/api/v1/check?domain=github.com"API Reference & Schemas
GET
/api/v1/check?domain={domain} Primary endpoint for inspecting certificate health. Returns validity dates, days/hours remaining, issuer, SANs, DNS CAA records, Dual-Stack status, and HTTP security headers.
Query Parameters
| Parameter | Type | Required | Description |
|---|---|---|---|
domain | string | Yes | Target fully qualified domain name (e.g. github.com, sub.example.com). |
HTTP Status Codes & Rate Limits
| Status | Meaning | Description |
|---|---|---|
200 OK | Success | Certificate inspected successfully or handled with structured failure diagnostics. |
400 Bad Request | Invalid Input | Missing domain parameter or malformed hostname syntax. |
429 Too Many Requests | Rate Limited | Exceeded 60 requests per minute per IP address. Check Retry-After header. |