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SSL

Quick Definition

SSL (Secure Sockets Layer) is the technology that encrypts the connection between your website and its visitors. Today it technically runs on TLS, but everyone still calls the certificate an "SSL certificate."

Let's Encrypt — a free SSL certificate provider used by millions of WordPress sites

What Is SSL?

SSL (Secure Sockets Layer) is a security protocol that creates an encrypted link between a web server and a browser. According to MDN Web Docs, SSL was the original standard — version 3.0 was released by Netscape in 1996 — but it has since been replaced by TLS (Transport Layer Security).

In practice, when people say "SSL certificate" or "SSL," they're referring to the modern TLS protocol. The name stuck even though the underlying technology changed. An SSL/TLS certificate enables HTTPS — the padlock icon in your browser's address bar that tells visitors the connection is secure.

According to the official WordPress documentation, HTTPS provides four key benefits:

  1. Performance — HTTPS actually makes your site faster thanks to HTTP/2, which only works over encrypted connections
  2. User trust — the padlock signals that your site cares about visitor privacy
  3. Payment security — essential for any site handling credit card data
  4. SEO — search engines penalize sites that don't use HTTPS

SSL in Practice

Getting an SSL certificate for your WordPress site is easier than ever:

  • Free from your host — SiteGround, Hostinger, Bluehost, and most reputable hosts include a free SSL certificate (via Let's Encrypt)
  • Free from Cloudflare — Cloudflare's free plan includes SSL
  • Paid certificates — only needed for Extended Validation (EV) certificates or specific business requirements

Once your certificate is installed, update your WordPress URLs from http:// to https:// in Settings → General. To force HTTPS on your admin area, add define('FORCE_SSL_ADMIN', true); to your wp-config.php file.

If you have mixed content issues (some resources loading over HTTP), plugins like Really Simple Security can fix them automatically.

Google Chrome displays a "Not Secure" warning for any site without HTTPS. This alone drives away visitors before they read a word.

Why It Matters

SSL isn't optional in 2026 — it's the baseline. Without it, you lose search rankings, visitor trust, and the ability to accept payments. The good news: it's free and takes minutes to set up. See our SSL setup guide and security guide for step-by-step instructions.

Related Terms

FTPFTP (File Transfer Protocol) is a method for uploading and downloading files between your computer and your WordPress hosting server. SFTP is the secure, encrypted version you should use instead.SFTPSFTP (SSH File Transfer Protocol) is the secure way to transfer files between your computer and your WordPress server. Unlike FTP, SFTP encrypts everything — your password, your data, and your commands.

Related Articles

How to Set Up SSL/HTTPS on WordPress (Free & Easy)SSL used to be optional. It's not anymore — Google penalizes sites without it, and Chrome slaps a 'Not Secure' warning on every page. The good news? It's free and takes about 10 minutes. Here's exactly how to set it up, plus how to fix the mixed content issues that trip up almost everyone.WordPress Security — The Complete Guide to Protecting Your SiteAfter 20 years of building WordPress sites, I've cleaned up more hacked sites than I care to remember. Most of those hacks were completely preventable. This is everything I know about keeping WordPress secure — no fear-mongering, just practical steps that actually work.Best WordPress Hosting in 2026 — Tested and ComparedI've tested every major WordPress host over the past decade. Here are my honest picks for 2026, with real performance data, pricing breakdowns, and recommendations for every budget.
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