SSL Certificate Checker
Check SSL/TLS certificate details for any website. View issuer, validity dates, certificate grade and security status.
Expires in days
📜 Certificate Details
📅 Validity Period
🌐 Subject Alternative Names
About SSL Certificate Checker
The SSL Checker is a free online diagnostic utility for network professionals, sysadmins, and curious users. Check SSL/TLS certificate details for any website. View issuer, validity dates, certificate grade and security status. Run checks instantly without installing any software — the SSL Checker talks to public services and returns results in a clean, readable format. When the SSL Checker queries external endpoints, we forward only the minimum data required and never log sensitive responses. Perfect for quick troubleshooting, SEO audits, or verifying infrastructure before a launch.
Use Cases
How to use
Type the domain whose certificate you want to inspect into the search box, for example example.com; https:// and www are removed for you.
Click Check SSL to fetch the live certificate straight from that server.
Read the grade card on the left: A+ for TLS 1.3, A for TLS 1.2, C when fewer than 30 days remain and F when the certificate is invalid or expired.
Check Certificate Details for issuer, subject, serial number, signature algorithm, key size and protocol, and Validity Period for the Valid From and Valid Until dates.
Scan the Subject Alternative Names list to confirm every hostname the certificate covers, then click Copy JSON to keep the full result.
Pro Tips
- Run the SSL Checker from a different network (mobile data vs. Wi-Fi) to compare results and spot location-specific issues.
- Re-run the SSL Checker a few minutes later if results look odd — transient DNS or routing glitches are common.
- Compare against a known-good domain to confirm that unexpected results are not just normal behavior.
- Screenshot or copy results when filing a support ticket — having the raw SSL Checker output speeds up debugging.
- Combine the SSL Checker with our other network tools (DNS, SSL, headers) for a full picture of a target endpoint.
Frequently Asked Questions
Yes, the SSL Checker is free to use with no signup, API key, or rate-limit surprises for normal use.
We keep minimal request logs for abuse prevention. We do not log or resell the content of your queries or the responses.
No. For security, the SSL Checker blocks private IP ranges, localhost, and cloud metadata endpoints to prevent SSRF abuse.
The SSL Checker runs each query in real time, so the output reflects the current state of the target at query time, subject to caching along the network path.
The SSL Checker is a web interface for occasional checks. For bulk or automated use, consider dedicated APIs or command-line tools.
Yes. The layout adapts to phones and tablets so you can run checks anywhere.