SSL Certificate Checker API GET

SSL Checker inspects a website's SSL certificate. It returns the certificate details plus derived signals — whether it is currently valid or expired, how many days until it expires, whether it expires soon, and whether it is self-signed.

Try it — live request, no key required

Request

GETapi.apiverve.com/v1/sslchecker

Verification

Format

No key required to try it. Get a key to use it in your app.

200 OK

{
  "status": "ok",
  "error": null,
  "data": {
    // SSL Certificate Checker response payload
  }
}

About the SSL Certificate Checker API

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.

What people use it for

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

Ways to call it

One endpoint, many ways in — REST with JSON, XML, YAML and CSV, plus GraphQL and an MCP interface for AI agents.

JSON: Default REST response
XML: Markup format
YAML: Human-readable
CSV: Tabular export
GraphQL: Query language
MCP: For AI agents

View all integrations →

Other ways to use SSL Certificate Checker

Same data, same APIVerve account, same credit balance — one key works on all of them.

Give it to an AI agentConnect over MCP and your agent calls it as a native tool — Claude, Cursor, ChatGPT.on VerveKit Google Sheets or ExcelA =VERVE() formula fills a column — no script, no export, recalculates in place.on VerveSheets Ground an agent on itA cited, machine-checkable fact your model can't produce on its own.on VerveContext

Questions.

Common questions about the SSL Certificate Checker API.

Read the docs →

What does the SSL Certificate Checker API do?

How do I authenticate SSL Certificate Checker API requests?

Pass your API key in the x-api-key header over HTTPS. One key works across all 300+ APIVerve APIs — there are no per-endpoint credentials.

How much does the SSL Certificate Checker API cost?

Each call spends 10 credits from your shared pool. The free tier includes 200 credits every month, and paid plans add more headroom.

How fast is the SSL Certificate Checker API?

Response time depends on the endpoint — the p50 through p99 latency for this API is published on this page. Requests are served over HTTPS through a global edge network.

What response formats does the SSL Certificate Checker API support?

JSON by default, plus XML and YAML via the format parameter. GraphQL and an MCP interface for AI agents are available across the catalog.

What HTTP method does the SSL Certificate Checker API use?

GET over HTTPS, following standard REST conventions with a consistent { status, error, data } response envelope.

Request parameters — GET /v1/sslchecker

Sent in the query string. Premium parameters are accepted on every plan but only take effect on plans that include them. Anything not listed here is dropped rather than passed through.

Required

Parameter	Type	Example	Description
`domain`Required	string	`ebay.com`	The domain of the website to check the SSL certificate of domain

Example request

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

Authentication

Send your key in the x-api-key header. That is the only auth step — no token exchange, and no per-endpoint scope to configure.

Header	When	Value
`x-api-key`Required	Every request	Your API key. Header names are case-insensitive, so `X-API-Key` is the same header.
`Authorization`Alternate	Instead of the above	`Bearer <key>` — for clients that only expose bearer auth. Resolves to the same account and the same billing.

401 is the only auth verdict

A 401 means the key is missing, invalid or expired. A 403 means the key is valid but not permitted here — blocked by a key restriction or an IP allow-list. Running out of credits is a 429.

Response — GET /v1/sslchecker

Every APIVerve endpoint returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape.

Sample response

{
  "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.

Field	Type	Example	Description
`subject`Premium	object	`{...}`	Certificate subject information including country, state, organization, and common name
`C`Premium	string	`"US"`	Country code of the certificate subject
`ST`Premium	string	`"California"`	State or province of the certificate subject
`O`Premium	string	`"eBay, Inc."`	Organization name of the certificate subject
`CN`Premium	string	`"ebay.com"`	Common name of the certificate subject domain
`issuer`Premium	object	`{...}`	Certificate issuing authority information including country, organization, and common name
`C`Premium	string	`"GB"`	Country code of the certificate issuer
`O`Premium	string	`"Sectigo Limited"`	Organization name of the certificate issuing authority
`CN`Premium	string	`"Sectigo Public Server Authentication CA OV R36"`	Common name of the certificate authority
`subjectaltname`Premium	string	`"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:e…`	Alternative subject names included in the certificate
`infoAccess`Premium	object	`{...}`	Information access extension with CA issuers and OCSP URIs
`CA Issuers - URI`Premium	array	`[http://crt.sectigo.com/SectigoPublicServerAuthenticationCAOVR36.crt]`	URLs to CA issuer certificates for validation
`OCSP - URI`Premium	array	`[http://ocsp.sectigo.com]`	Online Certificate Status Protocol URLs for validation
`ca`	boolean	`false`	Indicates if certificate is a certificate authority
`bits`	number	`2048`	Key size in bits representing certificate strength
`valid_from`	string	`"Jul 28 00:00:00 2025 GMT"`	Certificate validity start date and time in GMT
`valid_to`	string	`"Jul 28 23:59:59 2026 GMT"`	Certificate validity end date and time in GMT
`serialNumber`Premium	string	`"99F408949A6416EDC3B8F5EC77B2EBE5"`	Unique serial number of the SSL certificate
`domain`	string	`"ebay.com"`	Domain name the certificate was checked for
`isExpired`	boolean	`false`	Whether the certificate is past its valid_to date
`isValid`	boolean	`true`	Whether the current time is within the certificate's validity window (valid_from to valid_to)
`daysUntilExpiry`Premium	number	`20`	Whole days until the certificate expires (negative if already expired)
`isExpiringSoon`Premium	boolean	`true`	Whether the certificate expires within the next 30 days
`isSelfSigned`Premium	boolean	`false`	Whether the certificate is self-signed (subject and issuer are the same entity), which browsers do not trust

Response headers

Every response carries your balance, so your own code always knows where it stands without polling anything. All four are exposed to browsers through CORS.

Header	What it carries
`x-api-remaining-credits`	Credits left in the current cycle
`x-api-credits-used`	Credits spent in the current cycle
`x-api-max-credits`	The allowance for the cycle
`x-api-version`	Version of the endpoint that answered

Errors

Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change.

Status	Meaning	What to do
`400`	Input was rejected	Read `error`; it names the parameter that has to change.
`401`	Key missing or invalid	Check the header name and the key value.
`403`	Key valid, but not permitted here	A key restriction or an IP allow-list — never a bad key.
`429`	Rate limited, or out of credits	Read `error` to tell them apart, then back off or top up.

What a call costs — 10 credits per call

Credits are shared across every APIVerve API — one balance, one key, one bill. Failed requests never count against it, so a rejected input costs nothing.

Plan	Per month	Credits	SSL Certificate Checker calls	Per 1,000 calls
Free	Free	200	20	Free
Starter	$29.99	200,000	20,000	$1.50
Pro	$99.99	1,000,000	100,000	$1.00
Mega	$299.99	4,000,000	400,000	$0.75

Calls are what the credits buy at this API's rate — spend them here, on any of the other APIs, or across both. Nothing is reserved per endpoint.

Compare all pricing tiers →

Call it from cURL — GET /v1/sslchecker

No SDK to install — this is a plain HTTPS call to /v1/sslchecker with your key in the x-api-key header. Swap in a real key and it runs as-is.

cURL

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curl "https://api.apiverve.com/v1/sslchecker" \
  -H "x-api-key: YOUR_API_KEY"

Resources

GitHubapiverve/sslchecker-apiSource, issues and the examples this page is built from.ReferenceSSL Certificate Checker API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/sslcheckernpm apiverve-sslcheckerPyPI APIVerve.API.SSLCertificateCheckerNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Node.js — GET /v1/sslchecker

Install the Node.js SDK, then call the SSL Certificate Checker API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.

Install — npm

npm install @apiverve/sslchecker

Node.js

const res = await fetch("https://api.apiverve.com/v1/sslchecker", {
  headers: { "x-api-key": "YOUR_API_KEY" },
});
const { data } = await res.json();
console.log(data);

Resources

npm@apiverve/sslcheckerThe published Node.js client, versioned and signed.GitHubapiverve/sslchecker-apiSource, issues and the examples this page is built from.ReferenceSSL Certificate Checker API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

apiverve-sslcheckerPyPI APIVerve.API.SSLCertificateCheckerNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Python — GET /v1/sslchecker

Install the Python SDK, then call the SSL Certificate Checker API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.

Install — PyPI

pip install apiverve-sslchecker

Python

import requests

res = requests.get(
    "https://api.apiverve.com/v1/sslchecker",
    headers={"x-api-key": "YOUR_API_KEY"},
)
print(res.json()["data"])

Resources

PyPIapiverve-sslcheckerThe published Python client, versioned and signed.GitHubapiverve/sslchecker-apiSource, issues and the examples this page is built from.ReferenceSSL Certificate Checker API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/sslcheckernpm APIVerve.API.SSLCertificateCheckerNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from C# / .NET — GET /v1/sslchecker

Install the C# / .NET SDK, then call the SSL Certificate Checker API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.

Install — NuGet

dotnet add package APIVerve.API.SSLCertificateChecker

C# / .NET

using var client = new HttpClient();
client.DefaultRequestHeaders.Add("x-api-key", "YOUR_API_KEY");

var json = await client.GetStringAsync("https://api.apiverve.com/v1/sslchecker");
Console.WriteLine(json);

Resources

NuGetAPIVerve.API.SSLCertificateCheckerThe published C# / .NET client, versioned and signed.GitHubapiverve/sslchecker-apiSource, issues and the examples this page is built from.ReferenceSSL Certificate Checker API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/sslcheckernpm apiverve-sslcheckerPyPI

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Go — GET /v1/sslchecker

No SDK to install — this is a plain HTTPS call to /v1/sslchecker with your key in the x-api-key header. Swap in a real key and it runs as-is.

req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/sslchecker", nil)
req.Header.Set("x-api-key", "YOUR_API_KEY")

res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))

Resources

Also published for

@apiverve/sslcheckernpm apiverve-sslcheckerPyPI APIVerve.API.SSLCertificateCheckerNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from PHP — GET /v1/sslchecker

No SDK to install — this is a plain HTTPS call to /v1/sslchecker with your key in the x-api-key header. Swap in a real key and it runs as-is.

PHP

$ch = curl_init("https://api.apiverve.com/v1/sslchecker");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, ["x-api-key: YOUR_API_KEY"]);

$response = curl_exec($ch);
echo $response;

Resources

Also published for

@apiverve/sslcheckernpm apiverve-sslcheckerPyPI APIVerve.API.SSLCertificateCheckerNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Ruby — GET /v1/sslchecker

No SDK to install — this is a plain HTTPS call to /v1/sslchecker with your key in the x-api-key header. Swap in a real key and it runs as-is.

Ruby

require "net/http"

uri = URI("https://api.apiverve.com/v1/sslchecker")
req = Net::HTTP::Get.new(uri)
req["x-api-key"] = "YOUR_API_KEY"

res = Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) { |h| h.request(req) }
puts res.body

Resources

Also published for

@apiverve/sslcheckernpm apiverve-sslcheckerPyPI APIVerve.API.SSLCertificateCheckerNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

All articles →

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SSL Certificate Checker API GET

Try it — live request, no key required

About the SSL Certificate Checker API

What people use it for

Ways to call it

Other ways to use SSL Certificate Checker

Questions.

Request parameters — GET /v1/sslchecker

Required

Authentication

Response — GET /v1/sslchecker

Response fields

Response headers

Errors

What a call costs — 10 credits per call

Call it from cURL — GET /v1/sslchecker

Resources

Also published for

Call it from Node.js — GET /v1/sslchecker

Resources

Also published for

Call it from Python — GET /v1/sslchecker

Resources

Also published for

Call it from C# / .NET — GET /v1/sslchecker

Resources

Also published for

Call it from Go — GET /v1/sslchecker

Resources

Also published for

Call it from PHP — GET /v1/sslchecker

Resources

Also published for

Call it from Ruby — GET /v1/sslchecker

Resources

Also published for

Zero-code embed — one snippet, no backend

Changelog — SSL Certificate Checker API

Domain Data

Related articles

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