Guides
Understand, renew and troubleshoot your SSL certificates, step by step.
11 guides match “free certificate”.
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Tutorials Reading time: 3 min
Creating a free SSL certificate with Let's Encrypt and Certbot
Install Certbot, get a certificate for Nginx or Apache, handle wildcards and make sure automatic renewal really works.
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Tutorials Reading time: 2 min
Checking an SSL certificate's expiration date
Four ways to find a certificate's expiration date: browser, online tool, OpenSSL and the file on the server.
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Fundamentals Reading time: 4 min
Understanding SSL/TLS certificates
What an SSL certificate really is, what it contains, who issues it, and why it always ends up expiring.
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Tutorials Reading time: 4 min
How to renew your SSL certificate
How to renew a certificate without downtime, whether you use Let's Encrypt, a paid certificate or a host that handles it for you.
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Fundamentals Reading time: 3 min
SSL certificates: validity is dropping to 47 days
200 days in 2026, 100 days in 2027, 47 days in 2029. The timeline, what changes for Let's Encrypt and paid certificates, and how to prepare.
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Troubleshooting Reading time: 3 min
NET::ERR_CERT_DATE_INVALID error: causes and fixes
What the "Your connection is not private" error tied to the certificate date means, how to tell whether the problem is on the site or the visitor's side, and how to fix it.
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Fundamentals Reading time: 3 min
Let's Encrypt no longer sends expiration emails: how to stay informed
Since June 4, 2025, Let's Encrypt no longer warns you before a certificate expires. Why this safety net is gone, and how to replace it.
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Security Reading time: 4 min
SSL/TLS security best practices
Protocols, keys, HSTS headers, redirects and certificate monitoring: the checklist for a solid HTTPS setup.
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Tutorials Reading time: 3 min
Adding a domain to monitor
Add a domain in seconds, understand the information displayed and what happens next.
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Tutorials Reading time: 3 min
Importing multiple domains at once (CSV)
Prepare a CSV file, import it and understand the result: duplicates, plan limits and skipped rows.
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Tutorials Reading time: 4 min
Setting up your expiration alerts
Choose the channels (email, Slack, Telegram, webhook), when reminders go out and who gets them, and turn on reports.
A certificate to check right now?
The free checker shows its expiry date, issuer and covered domains.