curl "https://domscan.net/v1/certificates?domain=example.com"
Example Response
{
"domain": "example.com",
"certificates": [
{
"issuer": "Let's Encrypt",
"serial": "0a:1b:2c:3d:4e:5f",
"not_before": "2024-01-01T00:00:00Z",
"not_after": "2024-04-01T00:00:00Z",
"san": ["example.com", "www.example.com"],
"fingerprint_sha256": "AB:CD:EF..."
}
],
"total_certificates": 1,
"has_valid_cert": true
}
Key Features
CT Log Monitoring
Query public Certificate Transparency logs for any domain.
Certificate History
View historical certificates issued for a domain.
Issuer Tracking
Track which Certificate Authorities have issued certs for your domain.
Expiration Alerts
Identify expiring certificates before they cause outages.
SAN Coverage
See all Subject Alternative Names covered by each certificate.
Security Detection
Detect unauthorized or suspicious certificate issuance.
Fingerprint Verification
Verify certificate authenticity using SHA-256 fingerprints.
Compliance Monitoring
Ensure certificates meet security policy requirements.
Frequently Asked Questions
Certificate Transparency (CT) is a system where Certificate Authorities publicly log all SSL/TLS certificates they issue. This allows domain owners and security researchers to monitor for unauthorized certificates.
Monitoring helps detect: unauthorized certificates (potential MitM attacks), certificate expiration before it causes outages, compliance with security policies, and historical certificate changes.
We query live CT logs, so data is typically current within hours of certificate issuance.
Yes! You can monitor for certificates issued to domains similar to your brand, which could indicate phishing attempts.
Monitor SSL Certificates
Start for free with 10,000 credits per month. Start checking domains in seconds.
View Full API Documentation