1
Renew before it expires
Set the renewal to run well before the valid-to date, and confirm it actually completed.
TLS and domain
SSL certificate checker
Check a certificate issuer, validity dates and days to expiry.
Sample result Valid
moveinsights.co.uk
TLS certificate
Issuer Let's Encrypt R3
Valid from 2 Jun 2026
Valid to 31 Aug 2026
70 days
until expiry
Renews automatically on a 90-day cycle.
78%
Your result
What this checks
The certificate behind the padlock
An SSL certificate proves a site is who it says it is and encrypts the traffic to it. Every certificate has an issuer and a fixed validity window, after which browsers show a full-page security warning.
This checker connects to the domain over TLS, reads the certificate the server actually presents, and shows the issuer, the valid-from and valid-to dates and how many days are left until it expires.
Why it matters
An expired cert breaks the whole site
An expired certificate breaks the padlock and throws a full-page browser warning that scares visitors off. It is one of the most common and most avoidable ways a site looks broken.
Certificates renew on a cycle, often every 90 days with Let's Encrypt, so an unwatched renewal that fails is easy to miss until a client calls.
How to fix it
Three ways to keep the padlock green
2
Automate renewal
Use automated issuance (ACME, your host or CDN) so a human does not have to remember.
3
Check the whole chain
A missing intermediate certificate can fail on some devices even when it looks fine in your browser.
One of around two dozen checks
SSL certificate checker is one check
Janitor watches SSL validity and expiry automatically across every client site and puts it in a branded report you can send.
Keep reading
Related tools and guides
FAQ
SSL certificate checker FAQ
How does this checker read the certificate?
It connects to the domain over TLS, the same way a browser does, reads the certificate the server presents, and reports the issuer, the validity dates and the days remaining. Checking the full chain and warning you ahead of a renewal are part of the scheduled check inside Janitor.
How often should I check SSL?
Continuously, ideally with a warning 30 days out. A one-off check tells you about today; monitoring tells you before the next renewal fails.
What if no certificate is found?
The site may be new, may not serve HTTPS, or may not be reachable from the checker. Confirm the site loads over https:// first, then try again.
Get started
Check it once, or watch it for every client
Janitor runs around two dozen checks on every site you manage and turns them into a branded report.
30-day free trial. No credit card required.