SSL Checker
Instantly check SSL/TLS certificate details for any domain. See expiry date, issuer, protocol version, cipher suite and all Subject Alternative Names.
Free SSL Certificate Checker — Verify HTTPS Instantly
An SSL certificate is essential for every website. It enables HTTPS, encrypts data between users and your server, and is required by Google as a ranking signal. An expired or misconfigured SSL certificate causes browsers to show a "Not Secure" warning, immediately damaging visitor trust and conversion rates.
This free SSL Checker lets you instantly verify the SSL certificate of any domain. Enter a URL and see the certificate status, expiry date, days until expiry, issuer, protocol version, cipher suite, and Subject Alternative Names (SANs). Use it to monitor certificate health before it expires.
Certificate expiry is one of the most common and preventable website outages. A single expired SSL certificate can take down an entire site for all users and generate hundreds of browser security warnings.
What Is an SSL Certificate?
SSL stands for Secure Sockets Layer, though the modern standard is actually TLS (Transport Layer Security). The term SSL has stuck as a general name for HTTPS certificates. An SSL certificate is a digital document issued by a Certificate Authority (CA) that binds a public encryption key to a domain name.
When a browser connects to a website with a valid SSL certificate, it establishes an encrypted connection using TLS. All data transmitted — login credentials, form submissions, payment information — is encrypted and cannot be read by third parties on the network.
Without SSL, data travels as plain text. Anyone on the same network, such as a public Wi-Fi hotspot, can intercept and read it. This is why SSL is non-negotiable for any site that handles user data.
Why SSL Matters for SEO
Google ranking signal. Google confirmed HTTPS as a ranking factor in 2014. Sites on HTTPS have a slight ranking advantage over equivalent HTTP sites.
Chrome security warnings. Google Chrome shows a "Not Secure" label in the address bar for all HTTP pages. This warning directly reduces user trust and increases bounce rate.
Referral data preservation. HTTPS to HTTPS referrals preserve source data in analytics. HTTP to HTTPS transitions strip referral data, making traffic appear as direct visits.
Required for modern web features. Service workers, progressive web apps, geolocation, camera, and microphone APIs all require HTTPS. Sites without SSL cannot use these features.
What the SSL Checker Shows You
Certificate validity. Whether the certificate is currently valid or has expired.
Expiry date and days remaining. Exactly when the certificate expires so you can plan renewal in advance.
Issuer. Which Certificate Authority issued the certificate — Let's Encrypt, DigiCert, Comodo, or another CA.
Protocol version. Whether the site uses TLS 1.2, TLS 1.3, or an older insecure version.
Subject Alternative Names. All domains covered by the certificate, important for wildcard and multi-domain certificates.
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Frequently Asked Questions
What does an SSL certificate do?
It encrypts data between users and your server, activates HTTPS, and protects sensitive information.
Does SSL affect Google rankings?
Yes. HTTPS is a confirmed Google ranking factor and sites without it show security warnings in Chrome.
How do I know if my SSL is expiring?
Enter your domain in this SSL Checker to see the exact expiry date and days remaining.
Is this tool free?
Yes. Completely free, no sign-up needed.