Free tool

SSL certificate checker

Get a point-in-time view of the public certificate served by a domain. Use it for diagnosis and monitoring for future changes.

Check domain

What it checks

Validity

Start date, expiry date, and days remaining at check time.

Identity

Subject, issuer, and alternative names presented by the endpoint.

Transport

Negotiated TLS version and connection validation outcome.

How to interpret the limits

Checks TCP port 443 only; other ports are configured in the product.

Results can vary by load balancer, network, and time.

It does not renew certificates or monitor future expiry.

Safe use and privacy

Enter only public domains you are authorized to review. Queries are not stored; private IPs, localhost, reserved ranges, and mixed destinations are blocked. Results are point-in-time public metadata.

Frequently asked questions

Is the queried domain stored?

No. The tool processes the lookup to respond and does not persist the domain or result.

Can I check an IP or internal service?

No. Only public domains are accepted; direct IPs and private, local, or reserved destinations are blocked.

Move from a check to monitoring

A spot check helps diagnosis. Monitoring keeps history and warns you when evidence changes.

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