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SSL certificate & domain expiry checker

See when a site’s SSL certificate and domain registration expire, who issued them, and whether the site is up right now.

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Get alerts before these expire — start free

SteadySite checks your sites around the clock and emails you before an SSL certificate or domain runs out, or the moment a site goes down. 10 monitors free, no credit card.

FAQ

About SSL & domain expiry

What happens when an SSL certificate expires?

Browsers show a full-page “Your connection is not private” warning, and most visitors leave. Online checkouts and forms stop working, and search engines may drop the page. Renewal is quick, but only if someone notices in time.

Why do domains expire?

A domain is registered for a fixed period, usually one year. If auto-renew is off or the card on file has expired, the domain lapses: the website and email stop working and the name can be bought by someone else.

How does this checker get its data?

The SSL expiry comes from the certificate the site serves, or from public certificate-transparency logs when it can’t be read directly. Domain expiry and registrar come from the official registry (RDAP, the successor to WHOIS). The status check is a single request to the homepage.

Is it really free?

Yes. No sign-up, no limits for normal use. If you want to be warned before something expires, a free SteadySite account monitors up to 10 sites.

Is there an API for this checker?

Yes. GET https://steadysite.dev/api/ssl-check?domain=example.com returns JSON with SSL expiry, domain expiry and HTTP status. No key needed; results are cached for 15 minutes and fresh lookups are limited to 15 per IP per 10 minutes. OpenAPI spec: https://steadysite.dev/openapi.json.

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