SSL Certificate Inspection

Retrieve and inspect the SSL/TLS certificate for a domain. Returns certificate details, validity dates, expiration status, connection security information, and an overall grade.

Endpoint

GET /api/v1/ssl/{domain}

Authentication

All requests require an API key passed via the X-Api-Key header.

Parameters

Parameter	Type	In	Required	Description
domain	string	path	Yes	Domain name to inspect

Response

{
  "domain": "example.com",
  "valid": true,
  "issuer": "CN=R3, O=Let's Encrypt, C=US",
  "subject": "CN=example.com",
  "serialNumber": "04:A3:B7:2F:01:C9:8E:5D:00:02:7A:F1",
  "validFrom": "2025-01-15T00:00:00Z",
  "validTo": "2025-04-15T23:59:59Z",
  "daysUntilExpiry": 64,
  "signatureAlgorithm": "SHA256withRSA",
  "subjectAlternativeNames": [
    "example.com",
    "www.example.com"
  ],
  "protocol": "TLSv1.3",
  "cipherSuite": "TLS_AES_256_GCM_SHA384",
  "chainLength": 3,
  "errorMessage": null,
  "grade": "A+",
  "warnings": []
}

Response Fields

Field	Type	Description
domain	string	The queried domain
valid	boolean	Whether the certificate is currently valid and trusted
issuer	string	Certificate issuer distinguished name
subject	string	Certificate subject distinguished name
serialNumber	string	Certificate serial number (hex-encoded)
validFrom	string	Certificate start date (ISO 8601)
validTo	string	Certificate expiry date (ISO 8601)
daysUntilExpiry	integer	Number of days until the certificate expires (negative if expired)
signatureAlgorithm	string	Signature algorithm used (e.g., SHA256withRSA)
subjectAlternativeNames	array	List of domain names covered by the certificate (SANs)
protocol	string	Negotiated TLS protocol version
cipherSuite	string	Negotiated cipher suite
chainLength	integer	Number of certificates in the chain (including root)
errorMessage	string	Error description if the connection or validation failed (null on success)
grade	string	Overall SSL grade (A+, A, B, C, F) based on certificate and connection quality
warnings	array	List of warning messages about potential issues (weak cipher, short validity, etc.)

Grade Scale

Grade	Criteria
A+	Valid cert, TLSv1.3, strong cipher, 90+ days until expiry
A	Valid cert, TLSv1.2+, strong cipher
B	Valid cert, minor issues (short expiry, older protocol)
C	Valid cert, significant issues (weak cipher, very short expiry)
F	Invalid, expired, or self-signed certificate

Example

curl -H "X-Api-Key: YOUR_API_KEY" \
  "https://api.iqxlookup.neivi.es/api/v1/ssl/google.com"

Notes

• The endpoint connects to port 443 of the target domain
• daysUntilExpiry is negative for expired certificates
• valid is false if the certificate is expired, self-signed, or the chain is untrusted
• When the SSL connection fails entirely, errorMessage contains the failure reason and most other fields will be null