SSL Certificate Checker

Overview

SSL Checker works by fetching the live SSL certificate of the website provided and returning its details — issuer, subject, validity dates and key strength — along with derived checks computed from the certificate: current validity, days until expiry, an expiring-soon flag, and self-signed detection.

Endpoint

One host, one path per API. The block below shows this call in four languages; every one of them is the same HTTP request. Making requests covers the timeouts, retries and parameter rules that apply to all of them. The SDKs wrap the same call in a typed client.

curl "https://api.apiverve.com/v1/sslchecker?domain=ebay.com" \
  -H "x-api-key: your_api_key_here"

const res = await fetch('https://api.apiverve.com/v1/sslchecker?domain=ebay.com', {
  headers: { 'x-api-key': 'your_api_key_here' },
});

if (!res.ok) throw new Error(`${res.status} ${await res.text()}`);

const { data } = await res.json();
console.log(data);

import requests

res = requests.get(
    "https://api.apiverve.com/v1/sslchecker?domain=ebay.com",
    headers={"x-api-key": "your_api_key_here"},
    timeout=15,
)
res.raise_for_status()

print(res.json()["data"])

package main

import (
	"fmt"
	"io"
	"net/http"
)

func main() {
	req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/sslchecker?domain=ebay.com", nil)
	req.Header.Set("x-api-key", "your_api_key_here")

	res, err := http.DefaultClient.Do(req)
	if err != nil {
		panic(err)
	}
	defer res.Body.Close()

	out, _ := io.ReadAll(res.Body)
	fmt.Println(string(out))
}

Replace your_api_key_here with the key from your dashboard. When the inputs arrive as a list rather than one at a time, batch requests run up to 200 of them through this same API in a single call.

Authentication

Send your key in the x-api-key header. That is the only auth step — there is no token exchange and no per-endpoint scope to configure. Authentication covers creating, rotating and revoking keys.

Parameters

Sent in the query string. Premium parameters are accepted on every plan but only take effect on plans that include them.

Response

Every API returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape. Response format covers the envelope, the other output formats and how premium fields are withheld.

{
  "status": "ok",
  "error": null,
  "data": {
    "subject": {
      "C": "US",
      "ST": "California",
      "O": "eBay, Inc.",
      "CN": "ebay.com"
    },
    "issuer": {
      "C": "GB",
      "O": "Sectigo Limited",
      "CN": "Sectigo Public Server Authentication CA OV R36"
    },
    "subjectaltname": "DNS:ebay.com, DNS:befr.ebay.be, DNS:benl.ebay.be, DNS:cafr.ebay.ca, DNS:e-bay.it, DNS:ebay.at, DNS:ebay.be, DNS:ebay.ca, DNS:ebay.ch, DNS:ebay.co.uk, DNS:ebay.com.au, DNS:ebay.com.hk, DNS:ebay.com.my, DNS:ebay.com.sg, DNS:ebay.de, DNS:ebay.es, DNS:ebay.fr, DNS:ebay.ie, DNS:ebay.in, DNS:ebay.it, DNS:ebay.nl, DNS:ebay.ph, DNS:ebay.pl, DNS:ebay.us, DNS:ebay.vn, DNS:wwww.ebay.co.uk, DNS:wwww.ebay.com, DNS:wwww.ebay.com.au, DNS:wwww.ebay.de, DNS:wwww.ebay.in, DNS:wwww.ebay.it",
    "infoAccess": {
      "CA Issuers - URI": [
        "http://crt.sectigo.com/SectigoPublicServerAuthenticationCAOVR36.crt"
      ],
      "OCSP - URI": [
        "http://ocsp.sectigo.com"
      ]
    },
    "ca": false,
    "bits": 2048,
    "valid_from": "Jul 28 00:00:00 2025 GMT",
    "valid_to": "Jul 28 23:59:59 2026 GMT",
    "serialNumber": "99F408949A6416EDC3B8F5EC77B2EBE5",
    "domain": "ebay.com",
    "isExpired": false,
    "isValid": true,
    "daysUntilExpiry": 20,
    "isExpiringSoon": true,
    "isSelfSigned": false
  }
}

Response fields

Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.

Errors

Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change. Error handling covers the full status list and which of them are worth retrying.

Use cases

Security Analysis

Use the SSL Checker API to check SSL certificates for security analysis. Use the data to identify vulnerabilities, detect threats, and enhance security

Website Monitoring

Check SSL certificates by using the SSL Checker API for website monitoring. Use the data to monitor certificates, track expiration dates, and ensure compliance

SEO Optimization

Use the SSL Checker API to check SSL certificates for SEO optimization. Use the data to improve rankings, enhance visibility, and boost performance

Web Development

Check SSL certificates by using the SSL Checker API for web development. Use the data to ensure security, optimize performance, and enhance user experience

Other ways to use SSL Certificate Checker

Set up SSL Certificate Checker on APIVerve, or reach the same source a different way. Your APIVerve account and credits work on all of them — one key, one balance.

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