Track SSL/TLS certificate expiration dates, get renewal reminders, and keep your website security current. Avoid downtime from expired certificates.
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SSL certificate expiration can cause website downtime, security warnings, and lost customer trust. Our SSL Certificate Expiry Calculator helps you track certificate validity, plan renewals, and maintain uninterrupted HTTPS security for your websites.
An SSL/TLS certificate is a digital credential that authenticates a website's identity and enables encrypted HTTPS connections. Every certificate carries a validity period defined by its Not Before and Not After dates; once the Not After date passes, browsers reject the certificate and show security warnings, breaking the site until it is renewed. Public certificates are now capped at a 398-day maximum lifetime, and many are issued for 90 days or less, so the days remaining is simply the Not After date minus today's date. Teams typically set renewal reminders 30 days before expiry to leave time for reissuance and deployment.
An admin checks how many days remain until a certificate expires so it can be renewed before it lapses
An ops team monitors expiry dates across multiple sites to avoid downtime caused by an expired certificate
A security auditor records remaining validity periods for all certificates as part of a compliance report
An engineer confirms a certificate's expiry date before scheduling a server migration to reissue it in time
Expired certificates trigger browser security warnings that block visitors from accessing your site.
Search engines penalize sites with expired or invalid SSL certificates, hurting your search visibility.
Security warnings erode customer confidence and can significantly impact conversion rates.
Many regulations (PCI-DSS, HIPAA) require valid SSL certificates for handling sensitive data.
For Let's Encrypt certificates (90-day validity), renew every 60 days. For commercial certificates (1-2 year validity), renew 30-60 days before expiration to allow time for validation and installation.
Browsers display security warnings like 'Your connection is not private' or 'NET::ERR_CERT_DATE_INVALID'. Most visitors will leave immediately, and search engines may temporarily deindex your site.
Yes! Let's Encrypt supports automated renewal via Certbot or ACME clients. Most hosting providers also offer auto-renewal for their certificates. Commercial certificates typically require manual renewal.
Let's Encrypt provides free 90-day DV (Domain Validation) certificates. Commercial certificates offer 1-2 year validity with better support. EV (Extended Validation) certificates show organization name in browsers but cost more.
Click the padlock icon in your browser's address bar, then view certificate details. You can also use command line: 'openssl s_client -connect domain.com:443 | openssl x509 -noout -dates'.