Open the SSL Certificate Checker
Check any website's SSL/TLS certificate: expiry date and days left, issuer, covered domain names, TLS version, key size and whether browsers trust it.
- Free to use
- No signup
- Nothing to install
- Works in any modern browser
example.com → valid, 62 days left, issued by a public CA, TLS 1.3. expired.badssl.com → “Certificate has EXPIRED”.Open the SSL Certificate Checker
Illustration. Open the tool for the real thing.
What is the SSL Certificate Checker?
An expired or misconfigured SSL/TLS certificate makes browsers show a scary warning and drives visitors away. This SSL checker connects to any public domain, retrieves its live certificate and shows whether it is valid and trusted, how many days remain until it expires, who issued it, which domain names it covers and which TLS version and cipher the server negotiated.
It also reports the public key type and size, signature algorithm, serial number and SHA-256 fingerprint, and tells you exactly why a certificate would fail in a browser — expired, not yet valid, name mismatch, self-signed or issued by an untrusted authority. Use it to monitor renewals, verify a fresh install, or check a site you are about to trust.
3 steps to your result
Open the tool and follow along. Nothing to install.
What you get
Days remaining with a clear valid / expiring / expired verdict.
Verified against the same trusted authorities browsers use.
Issuer, dates, names covered, key, signature, fingerprint.
See the TLS version and cipher in use.
AZRS tools are free to open and use.
It opens in your browser, so there is nothing to download.
Used for
Pick one to see how it fits.
Website owners and admins
Catch expiring certificates before visitors see warnings.
Try it freeHow it compares
A plain look at this tool next to the usual alternative.
| This seo tool | Desktop software | |
|---|---|---|
| Install | Nothing to install | Usually an app or program to install |
| Account | No signup | Depends on the product |
| Cost | Free to use | Free or paid, depends on the product |
Questions people ask
What is an SSL certificate?
A digital document that proves a website's identity and enables an encrypted HTTPS connection. Modern sites use TLS, the successor to SSL.
How do I know if the certificate is valid?
It must be within its dates, cover the domain name, and be issued by an authority browsers trust. This tool checks all three.
What does “not trusted” mean?
The certificate is self-signed, signed by an unknown authority, or the server did not send the full chain.
How long do certificates last?
Public certificates are now limited to about 13 months, and many (such as Let's Encrypt) last 90 days.
Can it check internal servers?
No. Only public internet hosts can be checked.
More free tools
Related to the SSL Certificate Checker.
Try the SSL Certificate Checker now
Check a domain's SSL/TLS certificate, expiry date, issuer and trust status. Free to use.
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