How do I check if an SSL certificate is valid?

Enter the domain at https://www.iplocatortools.com/ssl-checker and click Check SSL. The tool connects directly over TLS port 443 and inspects the live X.509 certificate chain.

What happens when an SSL certificate expires?

When an SSL certificate expires, web browsers (Chrome, Safari, Firefox) immediately block access with a full-screen security error (NET::ERR_CERT_DATE_INVALID), dropping 99% of visitor traffic.

What is the difference between DV, OV, and EV SSL certificates?

Domain Validated (DV) only verifies domain ownership (ideal for blogs/standard sites). Organization Validated (OV) verifies the legal business entity. Extended Validation (EV) requires rigorous background checks for enterprise banks and financial apps.

What are Subject Alternative Names (SANs) in SSL?

SANs allow a single SSL certificate to secure multiple distinct hostnames or subdomains (such as example.com, www.example.com, and api.example.com) under one encryption key.

Security Tool

SSL Certificate Checker

Verify any domain's SSL/TLS certificate — issuer, expiry date, days remaining, and protocol validity directly.

SSL Certificate Basics

What is SSL?

SSL/TLS encrypts data between browser and server. HTTPS requires a valid certificate from a trusted Certificate Authority.

Certificate Expiry

Certs expire after 90 days (Let's Encrypt) to 1 year. Expired certs cause browser security warnings — monitor expiry dates.

Certificate Authority

CAs like Let's Encrypt, DigiCert, and Cloudflare sign certificates. Browsers trust certificates from recognised CAs.

SANs & Wildcards

One cert can cover multiple domains via SANs. A wildcard cert (*.example.com) covers all subdomains automatically.

SSL Certificate — Frequently Asked Questions

Enter the domain at IPLocatorTools SSL Checker and click Check SSL. The tool shows whether the certificate is valid, who issued it, and when it expires.

SSL certificates have an expiry date — typically 90 days to 1 year. When a certificate expires, browsers show a security warning and visitors cannot connect securely. Most hosting providers auto-renew certificates, but you should monitor expiry dates for critical domains.

The SSL certificate issuer (Certificate Authority or CA) is the organization that verified and signed the certificate. Common issuers include Let's Encrypt (free, automated), DigiCert, Sectigo, and Cloudflare. Certificates from trusted CAs are accepted by all major browsers.

SANs (Subject Alternative Names) are additional domain names or subdomains covered by the same certificate. For example, a certificate for example.com might also cover www.example.com and api.example.com as SANs. Wildcard certificates cover all subdomains of a domain.

SSL (Secure Sockets Layer) is the older protocol, now deprecated. TLS (Transport Layer Security) is the modern replacement. The term SSL is still commonly used but all modern secure connections use TLS 1.2 or TLS 1.3. When people say SSL certificate they mean a certificate used for TLS encryption.

Why SSL/TLS Certificate Validation Matters for HTTPS Security (RFC 8446)

Transport Layer Security (TLS 1.3) is the cryptographic protocol that encrypts modern web traffic. When a client visits an HTTPS domain, an asymmetric cryptographic handshake verifies the website's identity using an X.509 digital certificate (RFC 5280) issued by an internationally accredited Certificate Authority (CA).

Failing to renew a certificate before its expiration causes browsers to display harsh warnings. Our live SSL checker reads the exact socket parameters directly from the remote web server to assess cryptographic strength, remaining validity window, and Certificate Transparency logs.

SSL / TLS Certificate Validation Types & Comparison

Compare validation tiers, certificate authorities, and renewal timelines:

Validation Level	Verification Scope	Issuing CAs	Validity Window
Domain Validation (DV)	Verifies control of DNS or HTTP token	Let's Encrypt, Cloudflare, cPanel	90 days (auto-renew)
Organization Validation (OV)	Verifies registered corporate entity & domain	DigiCert, Sectigo, GlobalSign	398 days max
Extended Validation (EV)	Rigorous legal, physical, and operational check	DigiCert, Entrust, Sectigo	398 days max
Wildcard Certificate (*.domain)	Secures base domain and all subdomains	Let's Encrypt (DNS-01), Commercial CAs	90 – 398 days

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