SSL Certificates & HTTPS
This overview explains what an SSL/TLS certificate does, which certificate type suits your website and how to enable HTTPS on your server with Let's Encrypt — via Nginx, Apache, IIS or Plesk. Without a valid certificate, modern browsers show a security warning.
What is an SSL/TLS certificate?
An SSL/TLS certificate is a digital file that does two things at once: it encrypts traffic between the server and browser (so nobody can intercept it), and it confirms that the server is authorized to use your domain. The padlock symbol in the address bar indicates that a valid certificate is present.
Which certificate is right for me?
| Certificate type | Cost | Best for |
|---|---|---|
| Let's Encrypt | Free | Websites, blogs, web apps — the first choice for most use cases |
| Commercial certificate | Paid | Organization Validation (OV), Extended Validation (EV), or when Let's Encrypt is not an option |
| Self-signed | Free | Internal services, development environments — browsers will show a warning |
For publicly accessible websites we recommend Let's Encrypt — it is free, automatically renewable, and trusted by all major browsers.
Important notes before installation
Domain must point to your server
The A record of your domain must point to your server's IP address before a certificate can be issued. Let's Encrypt verifies this automatically.
Ports 80 and 443 must be open
Port 80 (HTTP) must be reachable from the internet for Let's Encrypt to issue and renew certificates. Port 443 (HTTPS) is needed for actual operation.
Set up automatic renewal
Let's Encrypt certificates are currently valid for 90 days. Certbot automatically sets up a systemd timer or cron job for renewal — verify that it is active.
Plesk handles everything automatically
If Plesk is installed on your server, you can issue and renew SSL certificates directly in the Plesk panel — no command line required.
Guides
Let's Encrypt with Nginx
Install a free SSL certificate with Certbot on a Linux server running Nginx and set up automatic renewal.
View Guide →
Let's Encrypt with Apache
Install a free SSL certificate with Certbot on a Linux server running Apache and set up automatic renewal.
View Guide →
Let's Encrypt with IIS (Windows)
Install a free SSL certificate on a Windows server with IIS using Win-ACME and set up automatic renewal.
View Guide →
Let's Encrypt via Plesk
Issue and renew SSL certificates directly in the Plesk panel — no command line, fully automatic.
View Guide →