SSL Certificate Check before it expires
A direct connection to port 443 on your domain, reading the certificate itself, and showing the dates, the issuer, the protocol version and the list of domains it covers. No external service sits in the path.
- No sign-up
- Days left to expiry
- List of covered domains
Run the tool right here
How many days until the certificate expires, who issued it, and whether it covers your domain.
- What it costs Free
- Data source Our own server
- Access No sign-up
The short answer
A healthy SSL certificate is one that has not expired, was issued by a trusted authority, and covers exactly the name the visitor types in the address bar. If any of those three fails, the browser shows a red warning page and effectively nobody enters the site.
The most common failure we actually see is not expiry, it is incomplete coverage. The certificate was issued for example.com but the visitor types www.example.com, or the other way round. Both names have to be in the coverage list, and this tool prints that whole list, so it takes seconds to see where the problem is.
The second failure is quieter: a broken chain. The certificate is fine but the server does not send the intermediate certificate. The result is that the site opens in desktop Chrome and errors on an older Android phone or inside apps, and because the owner sees nothing wrong, it can go unnoticed for months.
An SSL certificate is a Google ranking signal, but not a big one. Its real effect is elsewhere: without the padlock the browser marks a payment form as insecure, and a visitor who reads about online fraud every day closes the page right there. You do not pay for an expired certificate in lost rankings, you pay in lost orders.
Where the data comes from
A direct TLS connection from our own server, no third-party service. One thing that matters for .ir domains: Let's Encrypt certificates last three months, and we have repeatedly seen their auto-renewal break silently on Iranian shared hosts with nobody noticing until the expiry moment. Take the "days remaining" number seriously.
When it helps
When the browser shows a security warning, or to learn about an expiry before it happens. An expired certificate means every visitor sees a red warning page and the bounce rate is effectively total.
Where it does not help
This tool reads the certificate, it does not assess the security of the site. A site can have a perfectly healthy certificate and at the same time a vulnerable plugin, a weak admin password and security headers switched off. The green padlock only says the connection is encrypted, not that the other end is trustworthy. For the wider view see our website security scan. One technical note: the result comes from our server, so if your site serves a different certificate to non-Iranian IPs, what you see here differs from what a visitor inside Iran sees.
One thing we learned using it
Let's Encrypt certificates last three months and are supposed to renew automatically. On Iranian shared hosts we have repeatedly seen that automatic renewal break silently, with no warning recorded anywhere, until the day the certificate expired and the site came up with a red page. If you are on that kind of host, look at the days-left number once a month; that single habit makes the silent failure visible.
What it costs
This tool runs on our own server and we buy no data for it, so it is free and stays free. It only carries a daily cap so a bot cannot swallow the whole capacity.
The daily cap is counted per visitor. If you need more, a free account raises your limit.
Questions about this tool
How many days before expiry should I worry?
If the certificate renews automatically, under 14 days means the automatic renewal has failed and you should look at it that same day. If you buy the certificate manually, start a month ahead so there is time to issue and install it.
Does a free certificate differ from a paid one for SEO?
Not at all. Google draws no distinction between free and paid certificates and the browser shows the same padlock. The difference is in insurance, support and organisation validation, not in rankings.
The certificate is healthy but the browser still warns. Why?
Usually mixed content: the page loads over https but something inside it, an image or a script, loads over http. The browser treats that as enough to drop the padlock. Check the URLs of the resources on the page.