SSL Certificate Checker
Inspect SSL certificate details, issuer, expiration date, key size, signature algorithm, and certificate chain for any website over a TLS connection. Fast, security-minded, and free to use.
Why Certificates Matter
TLS encrypts data transmitted between a browser and server, while the certificate helps authenticate the server's identity and establish the secure connection.
Website Identity
A valid TLS certificate helps establish encrypted HTTPS connections between a browser and server. This helps protect passwords, payment details, and other sensitive information from being read in transit.
Better Search Visibility
HTTPS is an important trust signal. Secure websites provide a better user experience and are more likely to meet modern search engine expectations.
User Trust
Visitors are more likely to stay on websites that display a secure HTTPS connection. SSL helps build confidence and reduces browser security warnings.
Encrypted Data Transmission
TLS connection encryption helps protect information while it travels between a visitor's browser and your server, mitigating unauthorized access or tampering during transmission.
🛡️SSL Certificate Checker
Enter a domain above to analyze its SSL certificate.
Want a Deeper Understanding of SSL Certificates?
We published a complete step-by-step guide covering how SSL certificates work, how to check SSL validity, certificate expiration dates, HTTPS security, common SSL errors, and how to fix SSL issues for free.
📘 Read Full SSL Certificate Guide →How It Works
Inspect any public website's SSL certificate in just four simple steps and receive a detailed SSL certificate report.
🌐 Enter a Domain
Enter a public website domain such as example.com. Do not include https://, http://, or any page URL.
🔍 Click "Check SSL"
Our checker connects over a TLS connection to retrieve publicly available certificate information.
📄 Review the Report
View certificate details, issuer, expiry date, public key details, and the certificate chain.
🛡️ Take Action
Renew expired certificates and review SSL/TLS configuration issues using the certificate details and SSL Labs.
🔒 SSL Certificate Summary (Example)
Example SSL Report
Security Measures in This SSL Checker
Our SSL Checker is designed with multiple security-minded layers to retrieve SSL certificate details over a TLS connection while mitigating risks.
SSRF Protection
Before connecting to a website, the tool checks whether the domain resolves to a public IP address. Domains pointing to private or reserved IP addresses (such as localhost or internal servers) are automatically blocked to mitigate Server-Side Request Forgery (SSRF) risks.
DNS Rebinding Mitigation
The checker resolves the domain name first and connects to the selected public IP while sending the original hostname through SNI. This reduces the risk of DNS rebinding during the connection process.
IPv4 & IPv6 Support
Our checker supports both IPv4 and IPv6 websites. It automatically selects the first safe public IP address available and retrieves SSL certificate information from the server over a TLS connection.
Rate Limiting
To protect the service from abuse, checks are limited to up to 20 SSL checks per minute per client IP. Cloudflare-aware IP detection helps limit automated abuse and excessive requests while keeping the service fast and reliable.
Your Privacy Matters
We do not store SSL certificate results as part of this tool. Your submitted domain is processed in real time to retrieve publicly available certificate information. Standard server or security logs may still apply according to our Privacy Policy.
- No SSL certificates are stored on our servers.
- Only publicly available certificate information is retrieved.
- No account, registration, or login is required.
- Certificate information is fetched in real time whenever you perform a check.
Common SSL Checker Errors
If the SSL Checker cannot retrieve a certificate, the error message below explains the most likely reason and how you can fix it.
Invalid Domain Name
HTTP 400The domain format is invalid or incomplete.
Solution: Enter only the domain name, such as example.com. Do not include https://, http://, or any page URL.
Domain Could Not Be Resolved
HTTP 404The domain does not resolve to a public IP address.
Solution: Check the spelling of the domain, verify that DNS records exist, and make sure the website is online.
Private or Reserved IP
HTTP 403The domain points to a private or reserved IP address.
Solution: For security reasons, localhost, internal servers, and private network addresses cannot be checked.
Secure Connection Failed
HTTP 502The server did not accept a secure SSL/TLS connection.
Solution: Verify that HTTPS is enabled, an SSL certificate is installed correctly, and port 443 is accessible.
Rate Limit Exceeded
HTTP 429Too many SSL checks were submitted within a short period.
Solution: Please wait about one minute before trying again. Rate limits allow up to 20 checks per minute per client IP.
SSL Checker FAQs
Find answers to the most common questions about SSL certificates, HTTPS security, and using our free SSL Checker.
Why does this tool link to SSL Labs?
A proper SSL/TLS configuration test is extremely complex and must be performed from a dedicated server. Our SSL Checker retrieves certificate information and links to Qualys SSL Labs for a deeper SSL/TLS configuration analysis.
What is a good SSL Labs grade?
SSL Labs grades reflect multiple aspects of a server's TLS configuration. An "A" or "A+" grade generally indicates a strong configuration, while a "C" grade or below usually indicates configuration or security weaknesses that should be reviewed.
My certificate is valid but my site shows "Not Secure". Why?
This usually happens because of mixed content. Your page loads over HTTPS but images, JavaScript, CSS, or other resources are still being loaded over HTTP. Update every resource to HTTPS to resolve the warning.
How do I check if my SSL certificate is expired?
Enter your domain name into our SSL Checker and click "Check SSL". The tool displays the expiry date, remaining validity period, issuer details, and certificate information.
What is the difference between SSL and TLS?
SSL is the older encryption protocol that has been replaced by TLS. Modern websites commonly use TLS 1.2 or TLS 1.3, while older SSL protocols are obsolete, although the term "SSL certificate" is still commonly used.
How often should I check my SSL certificate?
Check your SSL certificate at least once a month. If you use Let's Encrypt certificates, monitor them more frequently because they expire every 90 days.
What HTTP security headers should my website have?
Important security headers include HSTS, Content Security Policy (CSP), X-Frame-Options, and X-Content-Type-Options. These headers help protect your website against common security threats.
Does SSL affect my Google rankings?
Google has confirmed HTTPS as a lightweight ranking signal. HTTPS also helps provide a secure browsing experience, although it is only one of many factors used in Search.
What is a certificate chain and why does it matter?
A certificate chain links the server certificate to a trusted Certificate Authority. If the chain is incomplete or cannot be trusted, browsers may show certificate warnings even when the server certificate itself is within its validity period.