What Happens When an SSL Certificate Expires?
An SSL/TLS certificate has a validity period. When that period ends, browsers can stop treating the certificate as valid.
For the website owner, the important part is simple: visitors may see a security warning instead of the normal website.
The server may still be running
This is easy to misunderstand.
An expired certificate does not necessarily mean the web server has stopped responding.
You can have a website that is technically reachable but still presents an invalid certificate.
So uptime and certificate validity are two different things worth watching.
What might a visitor see?
The exact message depends on the browser and the certificate problem.
A visitor may see a warning explaining that the connection is not private or that the certificate is expired.
Some people will leave immediately.
That is especially uncomfortable for a business website where trust matters.
Why expiry is different from downtime
With downtime, the server or application may not be responding.
With certificate expiry, the server may respond but the browser does not accept the certificate as valid.
Both can make a website experience a serious problem, but they need different fixes.
How to avoid discovering it too late
The simple approach is to monitor the certificate and receive a warning before the expiry date.
VeePulse combines website uptime monitoring with SSL expiry monitoring so the person responsible for a small site does not have to remember to check both separately.
The current product uses a default SSL warning threshold of 14 days, and the threshold is configurable.