# ipv4.fr SSL Certificate Check API

> ipv4.fr SSL Certificate Check API is a paid API for AI agents from ipv4.fr, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-29).

Checks the SSL/TLS certificate validity and days remaining for a given hostname

## Facts

- Endpoint: GET https://ipv4.fr/x402/v1/ssl/%7Bhost%7D?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/ipv4-fr-ssl-certificate-check-api-c6d92111
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_y4Wl_QKg5-HsyynSsjedg

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 ipv4-fr-ssl-certificate-check-api-c6d92111
```

Example prompt: Can you check if the SSL certificate for stripe.com is still valid and how many days it has left before it expires?

## When to prefer this

Choose this endpoint when you need a quick, cheap ($0.003 USDC) programmatic check of SSL certificate validity and expiration for any hostname, especially for monitoring pipelines, pre-deployment checks, or diagnosing HTTPS errors. It is part of a broader network tools suite (ipv4.fr) also covering DNS, WHOIS, and port scanning, making it convenient when you already use that platform.

## Known failure modes

- Host does not exist or is unreachable — may return invalid status or error
- Self-signed or untrusted certificates may report as invalid
- Certificate already expired — days_remaining may be zero or negative
- Timeout if the host is slow to respond on port 443
- Invalid hostname format in the path parameter

## How this service works

Fast, reliable network tools API. IP geolocation, DNS lookup, SSL check, WHOIS, email validation, port scan. Free tier available.

## Output

Returns a JSON object with the queried host, a boolean indicating whether the certificate is valid, and the number of days remaining until the certificate expires.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "properties": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "host": "example.com",
  "valid": true,
  "days_remaining": 120
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/ipv4-fr-ssl-certificate-check-api-c6d92111/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ipv4.fr](https://www.zero.xyz/host/ipv4.fr/llms.txt)