Free tools › SSL checker
SSL checker
Enter a domain and we'll check its certificate now: who issued it, when it expires, which names it covers and whether a browser would accept it.
Never again hear from a customer that your certificate expired
A certificate expiry monitor emails you when the number of days you choose remain or if it stops being valid. It's included from the Basic plan up.
What is an SSL certificate and what is it for?
An SSL certificate (technically TLS today) is a file installed on a site's server that does two things: it encrypts the connection between the browser and the site (the padlock and "https"), and it proves the site is who it claims to be, because a trusted certificate authority signs it.
Certificates expire: today they last only a few months, and the maximum keeps getting shorter. When one expires, the browser shows a full-screen warning, visitors leave, and the integrations and APIs that connect to the site fail.
That's why it pays to check it with the tool on this page and, better yet, watch it with an expiry monitor that alerts you in advance.
Frequently asked questions
What is SSL?
SSL is the historical name of the protocol that encrypts the connection between a browser and a website. Today TLS is used, but people still say "SSL certificate".
What's the difference between SSL and TLS?
TLS is the modern, secure version of SSL. Current certificates work with TLS even though they're still called SSL.
How do I know whether a site's SSL certificate is valid?
Type the domain into the checker above: we tell you whether browsers accept it, who issued it, which names it covers and how many days it has left.
Are there free SSL certificates?
Yes: authorities like Let's Encrypt issue them at no cost. They're short-lived and renew automatically when configured well, which is why it pays to watch that renewal works.
What happens if my site's SSL certificate expires?
Browsers show a full-screen security warning and most visitors leave. Integrations and APIs that connect to your site stop working.
How do I find out before it expires?
With a certificate expiry monitor: we email you when the number of days you choose remain (14 by default) or if it stops being valid. It's included from the Basic plan up.
Do you store the domains I check?
No. The check runs on the spot and neither the domain nor the result is stored.