{"id":77605,"date":"2026-10-10T17:28:35","date_gmt":"2026-10-10T15:28:35","guid":{"rendered":"https:\/\/tremhost.com\/blog\/?p=77605"},"modified":"2026-10-10T17:28:35","modified_gmt":"2026-10-10T15:28:35","slug":"cloudflare-pro-ssl-tls-modes-explained-flexible-vs-full-vs-full-strict","status":"publish","type":"post","link":"https:\/\/tremhost.com\/blog\/cloudflare-pro-ssl-tls-modes-explained-flexible-vs-full-vs-full-strict\/","title":{"rendered":"Cloudflare Pro SSL\/TLS Modes Explained: Flexible vs Full vs Full (Strict)"},"content":{"rendered":"<p data-pm-slice=\"1 1 []\">HTTPS is essential for modern websites. It protects information travelling between a visitor&#8217;s browser and a website, helps establish trust and supports secure online transactions.<\/p>\n<p>However, when a website uses Cloudflare, HTTPS involves more than installing a certificate on the hosting server. Cloudflare sits between the visitor and the origin server, creating two separate connections that must be configured appropriately.<\/p>\n<p>If the SSL\/TLS settings are incorrect, a website may experience redirect loops, certificate errors or an insecure connection between Cloudflare and the origin server.<\/p>\n<p>Understanding the available SSL\/TLS modes helps website owners avoid these problems and make better use of Cloudflare&#8217;s security capabilities.<\/p>\n<h2>How HTTPS Works With Cloudflare<\/h2>\n<p>When a website uses Cloudflare&#8217;s proxy, a visitor&#8217;s request normally passes through two connections.<\/p>\n<p>The first connection runs from the visitor&#8217;s browser to Cloudflare. The second runs from Cloudflare to the origin server hosting the website.<\/p>\n<p>Each connection has its own encryption requirements.<\/p>\n<p>A valid certificate at Cloudflare does not automatically mean the origin server is correctly configured. Similarly, installing an origin certificate does not guarantee that visitors will receive a valid HTTPS connection.<\/p>\n<p>Cloudflare&#8217;s SSL\/TLS encryption mode determines how Cloudflare connects to the origin server. Choosing the appropriate mode is important for both security and compatibility.<\/p>\n<h2>What Is Cloudflare Flexible SSL?<\/h2>\n<p>Flexible SSL encrypts the connection between the visitor and Cloudflare, but the connection from Cloudflare to the origin server uses HTTP rather than HTTPS.<\/p>\n<p>This can be useful in limited situations where an origin server does not yet support HTTPS. However, it leaves the connection between Cloudflare and the origin server unencrypted.<\/p>\n<p>For websites handling customer information, login credentials or sensitive transactions, that limitation is significant.<\/p>\n<p>Flexible mode can also contribute to redirect loops if the origin server repeatedly redirects HTTP requests to HTTPS without correctly recognising the original visitor connection.<\/p>\n<p>For these reasons, Flexible should not be treated as the preferred long-term configuration for a business website.<\/p>\n<h2>What Is Cloudflare Full SSL?<\/h2>\n<p>Full mode encrypts both connections: the visitor-to-Cloudflare connection and the Cloudflare-to-origin connection.<\/p>\n<p>Unlike Full (Strict), Full does not require the origin server&#8217;s certificate to be trusted and valid in the same way. This means a certificate problem at the origin may not prevent Cloudflare from establishing the encrypted connection.<\/p>\n<p>Although Full provides encryption between Cloudflare and the origin, website owners should still ensure that the origin certificate is correctly configured.<\/p>\n<p>Encryption alone does not establish that the origin certificate has been properly validated.<\/p>\n<h2>What Is Cloudflare Full (Strict)?<\/h2>\n<p>Full (Strict) encrypts both connections and requires the origin server to present a certificate that Cloudflare can validate.<\/p>\n<p>This generally means using a valid certificate from a trusted certificate authority or an appropriate Cloudflare Origin CA certificate, subject to Cloudflare&#8217;s requirements.<\/p>\n<p>For most properly configured production websites, Full (Strict) is the preferred option because it combines encryption with origin certificate validation.<\/p>\n<p>Before switching modes, verify that the origin server has a suitable certificate installed and that it is valid for the hostname Cloudflare connects to.<\/p>\n<p>Changing to Full (Strict) without checking the origin certificate can cause Cloudflare to reject the origin connection and return an error.<\/p>\n<h2>Which SSL\/TLS Mode Should You Choose?<\/h2>\n<p>The appropriate mode depends on the website&#8217;s origin configuration, but the following comparison provides a useful starting point.<\/p>\n<table>\n<tbody>\n<tr>\n<th>Mode<\/th>\n<th>Browser to Cloudflare<\/th>\n<th>Cloudflare to origin<\/th>\n<th>Typical consideration<\/th>\n<\/tr>\n<tr>\n<td>Flexible<\/td>\n<td>Encrypted<\/td>\n<td>Unencrypted<\/td>\n<td>Limited use cases; origin traffic is not encrypted<\/td>\n<\/tr>\n<tr>\n<td>Full<\/td>\n<td>Encrypted<\/td>\n<td>Encrypted<\/td>\n<td>Origin certificate validation is less strict<\/td>\n<\/tr>\n<tr>\n<td>Full (Strict)<\/td>\n<td>Encrypted<\/td>\n<td>Encrypted and validated<\/td>\n<td>Preferred for properly configured production websites<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>For most business websites, the goal should be to configure a valid origin certificate and use Full (Strict).<\/p>\n<p>Do not change the mode blindly if the website is already experiencing an error. First identify whether the problem is related to certificate validity, server configuration, redirect rules or another issue.<\/p>\n<h2>How Incorrect SSL Settings Cause Redirect Loops<\/h2>\n<p>A redirect loop occurs when a browser is repeatedly redirected between URLs or protocols without reaching the intended page.<\/p>\n<p>One possible cause involves Flexible SSL. Cloudflare may receive an HTTPS request from a visitor but communicate with the origin server over HTTP. If the origin server then redirects that request to HTTPS, the resulting behaviour can create a loop depending on the server and application configuration.<\/p>\n<p>Other causes include conflicting WordPress settings, reverse-proxy configuration, server-level redirects and duplicate rules.<\/p>\n<p>If your website enters a redirect loop, review the Cloudflare encryption mode alongside the origin server&#8217;s HTTPS settings. Check that WordPress recognises the correct site URL and that the server handles forwarded HTTPS requests appropriately.<\/p>\n<p>Avoid adding more redirect rules until you understand which layer is creating the loop.<\/p>\n<h2>How to Troubleshoot Cloudflare SSL Errors<\/h2>\n<p>If a website displays an SSL-related Cloudflare error, begin by identifying the error code and determining whether the problem occurs between the visitor and Cloudflare or between Cloudflare and the origin server.<\/p>\n<p>Check the origin certificate&#8217;s validity, hostname coverage and expiry date. Confirm that the web server is configured to serve the correct certificate and that the origin is reachable through the expected route.<\/p>\n<p>Next, review the current SSL\/TLS mode and any recent changes to DNS, hosting or certificate configuration.<\/p>\n<p>If the error began after switching to Full (Strict), verify that the origin certificate meets the requirements before making further changes.<\/p>\n<p>Testing changes in a controlled manner is safer than repeatedly switching between modes without identifying the underlying issue.<\/p>\n<h2>Does Cloudflare Pro Automatically Fix SSL Problems?<\/h2>\n<p>No. Cloudflare Pro includes additional website security and performance capabilities, but purchasing a paid plan does not automatically correct every certificate, redirect or origin-server configuration problem.<\/p>\n<p>SSL\/TLS settings still need to match the website&#8217;s infrastructure.<\/p>\n<p>A business website with a valid origin certificate can generally use a stronger configuration than a site whose origin has not been prepared for HTTPS. The correct approach is to fix the underlying certificate and server settings rather than rely on a weaker mode indefinitely.<\/p>\n<p>Website owners should also monitor certificate expiry, verify DNS records and test the complete HTTPS journey after configuration changes.<\/p>\n<h2>Explore Cloudflare Pro Through Tremhost<\/h2>\n<p>Businesses looking to improve website security and performance can explore Tremhost&#8217;s Cloudflare offering.<\/p>\n<p>Tremhost offers a Cloudflare Pro-based security option from <strong>$9 per month<\/strong>. Visit the <a href=\"https:\/\/tremhost.com\/cloudflare\/\">Tremhost Cloudflare page<\/a> to review the available service details.<\/p>\n<p>Before choosing a provider, confirm what is included in the service and whether SSL\/TLS configuration assistance is part of the package.<\/p>\n<p>For broader assistance with protecting online infrastructure, businesses can also explore <a href=\"https:\/\/tremhost.com\/managed-cyber-security\/\">Tremhost&#8217;s managed cybersecurity services<\/a>.<\/p>\n<h2>Final Thoughts<\/h2>\n<p>Cloudflare&#8217;s SSL\/TLS modes determine how encrypted connections are established between visitors, Cloudflare and the origin server.<\/p>\n<p>Flexible encrypts only the visitor-to-Cloudflare connection. Full encrypts both connections but applies less stringent origin certificate validation. Full (Strict) encrypts both connections and validates the origin certificate.<\/p>\n<p>For most properly configured production websites, Full (Strict) is the preferred choice. However, it should be enabled only after confirming that the origin certificate and server configuration are correct.<\/p>\n<p>Understanding these differences helps website owners avoid common HTTPS problems while maintaining a stronger security configuration.<\/p>\n<p><strong>Explore Cloudflare protection through Tremhost:<\/strong> <a href=\"https:\/\/tremhost.com\/cloudflare\/\" data-rich-text-autolink=\"\">https:\/\/tremhost.com\/cloudflare\/<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>HTTPS is essential for modern websites. It protects information travelling between a visitor&#8217;s browser and a website, helps establish trust and supports secure online transactions. However, when a&hellip;<\/p>\n","protected":false},"author":226,"featured_media":77556,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"footnotes":""},"categories":[366],"tags":[],"class_list":["post-77605","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-cybersecurity"],"_links":{"self":[{"href":"https:\/\/tremhost.com\/blog\/wp-json\/wp\/v2\/posts\/77605","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/tremhost.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/tremhost.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/tremhost.com\/blog\/wp-json\/wp\/v2\/users\/226"}],"replies":[{"embeddable":true,"href":"https:\/\/tremhost.com\/blog\/wp-json\/wp\/v2\/comments?post=77605"}],"version-history":[{"count":1,"href":"https:\/\/tremhost.com\/blog\/wp-json\/wp\/v2\/posts\/77605\/revisions"}],"predecessor-version":[{"id":77606,"href":"https:\/\/tremhost.com\/blog\/wp-json\/wp\/v2\/posts\/77605\/revisions\/77606"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/tremhost.com\/blog\/wp-json\/wp\/v2\/media\/77556"}],"wp:attachment":[{"href":"https:\/\/tremhost.com\/blog\/wp-json\/wp\/v2\/media?parent=77605"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/tremhost.com\/blog\/wp-json\/wp\/v2\/categories?post=77605"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/tremhost.com\/blog\/wp-json\/wp\/v2\/tags?post=77605"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}