How to use Website SSL Checker
- Give Website SSL Checker a PEM certificate to work from.
- Press Parse certificate to run it locally in your browser.
- Read the subject, issuer, validity dates and expiry that Website SSL Checker lays out for you.
About this tool
Website SSL Checker is a static, client-side tool with no backend. Paste a PEM certificate and Website SSL Checker 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
What does Website SSL Checker do?
Use Website SSL Checker to check your input without installing anything; everything happens client-side.
Is Website SSL Checker free to use?
Yes — Website SSL Checker is completely free, with no usage limits.
Does Website SSL Checker upload my data?
No — Website SSL Checker processes everything locally in your browser, so nothing you enter is uploaded or stored.
How do I inspect a live site's certificate in Website SSL Checker?
Export the certificate from your browser's padlock as PEM and paste it into Website SSL Checker; it decodes the ASN.1/DER fields entirely on your device.
Does Website SSL Checker work on mobile?
Yes — Website SSL Checker is just a web page and runs on any modern browser, including phones and tablets.