How to use SSL Test
- Paste or load a PEM certificate into SSL Test.
- Click Parse certificate — SSL Test processes everything on your device.
- Review the subject, issuer, validity dates and expiry shown below.
About this tool
SSL Test runs entirely in your browser. Paste a PEM certificate and SSL Test parses the X.509 fields entirely on your device.
The expiry countdown is computed locally, and nothing about the certificate is transmitted. Your input never leaves the page, and no account or install is required.
Frequently asked questions
How do I use SSL Test?
SSL Test lets you check your input right in the browser, with the result shown instantly and nothing uploaded.
Does SSL Test cost anything?
No — SSL Test is completely free, with no sign-up and no hidden limits.
Is my input private in SSL Test?
Yes — your input never leaves your device; SSL Test does all the work in your browser.
How do I inspect a live site's certificate in SSL Test?
Export the certificate from your browser's padlock as PEM and paste it into SSL Test; it decodes the ASN.1/DER fields entirely on your device.
Can I use SSL Test without a connection?
Yes — after the first load SSL Test runs entirely offline.