# SSL/TLS Certificate Checker

> SSL/TLS Certificate Checker is a paid API for AI agents from api.strale.io, paid per call via x402, $0.0324/call, status unknown (last checked 2026-10-12).

Checks a domain's SSL/TLS certificate and returns issuer, validity dates, days until expiry, protocol version, cipher suite, and SAN entries.

## Facts

- Endpoint: GET https://api.strale.io/x402/ssl-check?utm_source=zero.xyz
- Price: $0.0324/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-strale-io-1c89ef1d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_jDIsAG2zs7dEESxJXpeI-

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability api-strale-io-1c89ef1d
```

Example prompt: Can you check the SSL certificate for stripe.com — I want to know the issuer, how many days until it expires, the TLS protocol version, and what SANs are listed?

## When to prefer this

Use this endpoint when you need quick, structured SSL/TLS certificate metadata for a domain — especially expiry monitoring, issuer verification, protocol/cipher auditing, or SAN coverage checks. Prefer over manual openssl commands or browser inspection when programmatic, agent-accessible output is needed.

## Known failure modes

- Domain not found or does not resolve — returns error indicating DNS failure
- Domain has no SSL certificate or serves on non-standard port — returns connection error
- Certificate is self-signed or invalid — may still return data but flagged accordingly
- Malformed domain input — returns validation error
- Timeout if domain is unreachable or slow to respond

## How this service works

Check a domain's SSL/TLS certificate. Returns issuer, validity dates, days until expiry, protocol version, cipher, and SAN entries.

## Output

Returns structured certificate data including the issuer organization, certificate validity start and end dates, number of days remaining until expiry, TLS/SSL protocol version (e.g. TLSv1.3), cipher suite in use, and the list of Subject Alternative Names (SANs) covered by the certificate.

## Example request

```json
{
 "domain": "example.com"
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "domain"
 ],
 "properties": {
  "domain": {
   "type": "string",
   "description": "Domain name (e.g. example.com)"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "valid": {
  "type": "boolean"
 },
 "domain": {
  "type": "string"
 },
 "issuer": {
  "type": "string"
 },
 "valid_to": {
  "type": "string"
 },
 "is_expired": {
  "type": "boolean"
 },
 "days_until_expiry": {
  "type": "integer"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-strale-io-1c89ef1d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.strale.io](https://www.zero.xyz/host/api.strale.io/llms.txt)