When managing your WordPress website, you may have noticed that it can be accessed using either HTTP or HTTPS. While both seem to display your site just fine, there are technical and security implications behind the scenes that you need to understand. This article breaks down how WordPress internally manages HTTP vs HTTPS requests and what you, as a site owner or client, should know to make informed decisions.

What Is the Difference Between HTTP and HTTPS?

• HTTP (HyperText Transfer Protocol) is the standard for data communication on the web.

• HTTPS (HTTP Secure) adds an extra layer of protection by encrypting data using SSL/TLS certificates.

While HTTP transfers data in plain text (which can be intercepted), HTTPS encrypts the connection between the user’s browser and the web server, ensuring secure transmission of sensitive information such as login credentials and contact form submissions.

How WordPress Detects HTTP vs HTTPS Internally

WordPress uses server variables and configurations to determine whether a visitor is accessing your website through HTTP or HTTPS.

Key Detection Mechanisms:

1. $_SERVER['HTTPS'] Variable
   WordPress checks this variable to determine the protocol:

   • If set to "on" or 1, it assumes HTTPS is in use.

   • If not set, it assumes HTTP.

2. Site URL and Home URL Settings
   Inside the WordPress database:

   • siteurl and home values must be set to either http://yourdomain.com or https://yourdomain.com.

   • These are used in internal links, redirections, and canonical URLs.

3. is_ssl() Function
   This internal function returns true if HTTPS is being used:

   if (is_ssl()) {
   // Perform secure operations
   }

   WordPress plugins and core features rely on this function to ensure that secure behavior (like secure cookies and form submissions) is applied only when HTTPS is detected.

Why the Protocol Matters to WordPress Functionality

1. Login and Admin Security
   When accessing wp-login.php or the admin dashboard (/wp-admin), HTTPS ensures that login credentials are not exposed. WordPress can enforce this using:

   define(‘FORCE_SSL_ADMIN’, true);

   This tells WordPress to force HTTPS on all admin pages.

2. Mixed Content Warnings
   If your site is loaded over HTTPS but contains links or media using HTTP, browsers may show warnings or block those elements. WordPress handles this by:

   • Rewriting URLs in content using HTTPS (via functions like wp_get_attachment_url).

   • Plugins like “Really Simple SSL” can help ensure all resources load over HTTPS.

3. Cookie Security
   WordPress uses SECURE and HTTPONLY flags for cookies when HTTPS is active. This prevents cookies from being accessed by malicious scripts or leaked over insecure connections.

4. Redirect Behavior
   If your WordPress site is configured for HTTPS but accessed via HTTP, WordPress will:

   • Attempt to redirect to the HTTPS version (based on siteurl and home).

   • This can be enforced with server rules (e.g., .htaccess or Nginx configs), but WordPress respects these values for internal redirection too.

What You Should Do as a Website Owner

Even if you’re not a developer, you can take the following steps to ensure your WordPress site properly handles HTTP and HTTPS:

1. Always Use HTTPS

Use HTTPS for all pages, not just the login or checkout. This improves security and boosts trust and SEO rankings.

2. Update WordPress Settings

Go to:
Settings → General
Update both WordPress Address (URL) and Site Address (URL) to use https://.

3. Force HTTPS Redirection

Use a plugin like “Really Simple SSL” or update your .htaccess file (for Apache servers) to redirect all HTTP traffic to HTTPS:

4. Check for Mixed Content

Use browser developer tools or tools like Why No Padlock to identify and fix insecure resource links.

5. Secure Cookies and Admin Pages

Add this line to your wp-config.php to enforce HTTPS in admin:

Common Scenarios and How WordPress Reacts

Final Thoughts

Understanding how WordPress handles HTTP vs HTTPS internally helps you make smarter choices about your site’s security, performance, and search engine visibility. By configuring your site properly, you not only protect your visitors’ data but also improve the trust and credibility of your brand online.

You don’t need to be a developer to take these steps a few simple changes in your WordPress settings and server configuration can ensure your site is always secure.