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Website HTTPS certificate checker

SSL Certificate Checker

Check SSL certificate details for any domain. View expiry date, issuer, common name, valid period, days left, SAN domains, domain match, and overall certificate status.

Expiry Check Issuer Details Domain Match

Verify HTTPS security quickly

Useful for website owners, developers, SEO teams, hosting migration, SSL renewal, and uptime checks.

Free SSL Certificate Checker Tool

Enter a domain name and check whether its SSL certificate is valid, expired, expiring soon, or mismatched.

Enter Domain

Enter domain only. Example: example.com or yourdomain.com
This tool checks the SSL certificate served on port 443. Results depend on your server connection and domain SSL setup.

SSL Result Summary

Ready to Check
Enter a domain name to inspect SSL expiry, issuer, SAN names, and HTTPS certificate status.
SSL result actions will appear after a successful check.
Not checked SSL Status
0 Days Left
Not checked Domain Match
0 SAN Domains

SSL Certificate Details

SSL certificate details will appear here after checking a domain.

Subject Alternative Names

SAN domains will appear here after checking SSL.

Quick Domain Examples

Renew SSL before expiry to avoid browser warnings, checkout issues, SEO trust problems, and broken HTTPS access.

Why Use an SSL Certificate Checker?

An SSL certificate checker helps you verify whether your website HTTPS certificate is active, trusted, valid, and not close to expiry.

Check SSL Expiry

Find the exact SSL expiry date and see how many days are left before the certificate expires.

View Issuer Details

Check which certificate authority issued the SSL certificate and what signature type is used.

Verify Domain Match

Confirm whether the certificate common name or SAN list matches the domain you entered.

What Is an SSL Certificate Checker?

An SSL certificate checker is a tool that connects to a website over HTTPS and reads the certificate information served by the domain. It helps confirm whether the certificate is valid, expired, expiring soon, or mismatched.

Website owners use SSL checks to avoid browser security warnings, payment page issues, login problems, and trust loss. Regular SSL monitoring is important for blogs, business websites, ecommerce stores, SaaS platforms, and client websites.

SSL Field Meaning Why It Matters
Valid From Certificate start date Shows when SSL became active
Valid To Certificate expiry date Helps renew before expiry
Issuer Certificate authority Shows who issued the SSL
Common Name Main certificate domain Helps check domain match
SAN Names Extra covered domains Useful for www and subdomains

How It Works

Check an SSL certificate in three simple steps.

Enter Domain

Type a domain name such as example.com. The tool automatically removes http, https, and URL paths.

Connect to SSL

The tool connects to the domain on HTTPS port 443 and captures the SSL certificate.

View Certificate Data

Check expiry, issuer, valid dates, common name, SAN domains, domain match, and SSL status.

SSL Certificate Checker FAQs

Common questions about SSL certificates, HTTPS security, and server requirements.

An SSL certificate checker reads a website certificate and shows expiry date, issuer, valid period, common name, SAN names, and status.
Expired SSL certificates can show browser security warnings and may break trust, logins, checkout pages, and HTTPS access.
No. This SSL checker uses PHP OpenSSL functions and does not require any external API or database.
It may fail if PHP OpenSSL is disabled, outbound SSL connections are blocked, the domain has no SSL, or the server blocks port 443 connections.
Domain mismatch means the SSL certificate common name or SAN list does not match the domain you checked.