Is your SSL valid - days left before visitors see a security warning.
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Is the certificate active right now?
Exact date and days remaining until renewal
Will Chrome, Firefox, Safari, Brave, and other browsers trust the full chain?
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TLS validation and expiry in plain terms
An expired SSL certificate triggers a full-screen warning in Chrome, Firefox, Safari, Brave, and other major browsers - most visitors leave without completing a purchase or sign-up. Our checker validates certificates against the same trust rules those browsers use.
A broken SSL chain or hostname mismatch triggers the same warnings even when a certificate looks valid on paper. A free SSL certificate checker lets you verify certificate trust and check SSL expiry before visitors see security warnings.
Run a one-time free SSL check after server changes or before renewals. Add the domain to TotalSiteControl monitoring for automated expiry alerts 30, 14, and 7 days before lapse.
Start free monitoring with email alerts. No credit card required.
Check any public domain in under a minute - no account needed.
Type the hostname visitors use, for example yourdomain.com or www.yourdomain.com. Subdomains work too - check the exact name that serves HTTPS.
Click Check SSL. We connect to the server over HTTPS and inspect the certificate, expiry date, issuer, and chain trust.
See whether the certificate is valid, how many days remain, and if browsers will trust the chain. Then renew, fix the chain, or turn on monitoring so you get alerts before expiry.
What browsers show - and how to fix it before visitors bounce.
Chrome and other browsers show a full-screen warning. Visitors leave, checkouts fail, and APIs may refuse HTTPS connections.
Issue a new certificate from your CA or ACME client, install it on the server, then re-check the same hostname. Turn on expiry alerts so this does not happen again.
The leaf certificate looks fine, but missing intermediate CA files make browsers reject the connection with the same security warning.
Upload the intermediate certificates your CA provides (fullchain, not leaf-only). Re-run the SSL check to confirm chain trust before promoting the change.
The certificate is valid for another name (for example apex vs www, or an old domain). Browsers warn even when the cert is not expired.
Use a certificate that covers every name visitors type - SAN or wildcard as needed. Check www and apex separately if they resolve to different hosts.
Certificate, DNS, and reachability history in one place.
Checks run from our servers - the same path users hit.
Turn a one-off check into monitoring in under a minute.
External probes so internal network blind spots do not hide issues.
Email and Telegram when something fails or is about to expire.
Start free - no credit card required to begin monitoring.
Start free monitoring with email alerts. No credit card required.
Quick habits that prevent browser warnings.
Certificates for yourdomain.com and www.yourdomain.com can differ. Run the SSL check on every public hostname that serves HTTPS.
Most browsers need intermediate certificates. After renewals, confirm chain trust with a fresh SSL check before you close the ticket.
Renew early and turn on monitoring alerts at 30, 14, and 7 days so a missed renewal does not become an outage.
Load balancers, reverse proxies, and CDNs can serve a different certificate than the origin. Verify the edge hostname after every TLS change.
It connects to a domain's HTTPS server, retrieves the TLS certificate, and reports whether it is valid, who issued it, when it expires, and if the certificate chain is trusted.
Yes. Enter any public domain and get instant results - no signup, no credit card, and no limit on one-off checks. Optional monitoring alerts are also free to start.
Browsers show this when HTTPS cannot be trusted - usually because the certificate expired, the chain is incomplete, or the certificate name does not match the hostname. Run a free SSL check on the exact URL visitors use (including www) to see which issue applies.
Browsers display security warnings and may block access entirely. Visitors lose trust, SEO can suffer, and API clients may fail until the certificate is renewed.
A certificate chain links your site certificate to a trusted root CA through one or more intermediate certificates. If intermediates are missing on the server, browsers may reject an otherwise valid certificate. Our checker validates the full chain, not just the expiry date.
It depends on the result: renew or reinstall if expired; upload missing intermediate certificates if the chain fails; install a certificate that includes the correct hostname if there is a name mismatch. After fixing, run the check again from the same hostname your users visit.
Yes - enter any hostname such as www.yourdomain.com or api.yourdomain.com. We connect to its HTTPS endpoint and inspect the certificate served for that name.
Check manually before renewals or after server changes. For production sites, automated monitoring with expiry alerts is recommended so you are notified before certificates lapse.