SSL Certificate Checker
Check a domain's SSL certificate — issuer, validity dates, and days remaining before it expires.
Frequently Asked Questions
Is the SSL Certificate Checker really free?
Yes — unlimited use, no signup, no credit card. We built these tools to help you audit sites without paying for a data subscription.
Does this tool store or share the URLs I check?
No. Each check runs live and we don't save your input. We keep a short-lived rate-limit counter (by IP) purely to prevent abuse; it is not linked to your results.
How accurate are the results?
This tool reads live, public data directly from the page or domain you enter — it does not rely on a paid third-party database, so it reflects exactly what is publicly visible right now.
An SSL/TLS certificate is what enables HTTPS — the padlock in the browser — encrypting traffic between your site and its visitors. Google uses HTTPS as a lightweight ranking signal, browsers actively warn users away from non-HTTPS sites, and an expired certificate can make a site show a full-page security warning that scares visitors off entirely. This tool inspects a domain's live certificate and, crucially, tells you how many days remain before it expires.
How to Use This Tool
Enter a domain and click Check SSL. The tool opens a secure connection to the domain and reads its certificate details.
What This Tool Checks
The certificate's issuer (the certificate authority), the domain it was issued for, its valid-from and valid-to dates, and the number of days remaining before expiry.
Understanding Your Results
A certificate with plenty of days remaining and a recognized issuer is healthy. Fewer than ~14 days remaining is a warning to renew now — especially important if you don't have automatic renewal configured. An expired certificate is urgent: visitors will see browser security warnings until it's renewed.
How to Fix Common Problems
Most modern hosts and certificate providers (including free Let's Encrypt certificates) auto-renew, but auto-renewal can silently fail — which is exactly why checking days-remaining matters. If a certificate is expiring, renew it through your host or certificate provider. If auto-renewal keeps failing, investigate why rather than manually renewing every 90 days forever.
SEO Best Practices
Set up automatic certificate renewal and, on top of that, monitor expiry (this tool, or an uptime service that alerts on cert expiry) as a safety net — auto-renewal failures are common enough that a backup check saves you from an embarrassing outage. Ensure your whole site forces HTTPS via redirects.
Example
Checking a domain shows its Let's Encrypt certificate expires in 4 days — a sign auto-renewal has failed and needs attention before visitors start seeing security warnings.
Common Mistakes to Avoid
Don't assume auto-renewal is working just because it worked last time — it fails silently more often than people expect. Don't ignore a certificate that covers the wrong hostname (e.g. covers example.com but not www.example.com), which causes warnings on the uncovered version.
Related SEO Guides
Strong technical setup plus quality backlinks is how pages rank — we handle the links.