diff --git a/app/assets/stylesheets/common/base/topic-post.scss b/app/assets/stylesheets/common/base/topic-post.scss
index adee44fcc0d..80668a280b0 100644
--- a/app/assets/stylesheets/common/base/topic-post.scss
+++ b/app/assets/stylesheets/common/base/topic-post.scss
@@ -53,34 +53,34 @@
   }
 
   h1 {
-    font-size: $font-up-4;
-  }
-
-  h2 {
     font-size: $font-up-3;
   }
 
-  h3 {
+  h2 {
     font-size: $font-up-2;
   }
 
-  h4 {
+  h3 {
     font-size: $font-up-1;
   }
 
-  h5 {
+  h4 {
     font-size: $font-0;
   }
 
-  h6 {
+  h5 {
     font-size: $font-down-1;
   }
 
+  h6 {
+    font-size: $font-down-2;
+  }
+
   a { word-wrap: break-word; }
   ins { background-color: dark-light-choose($success-low, scale-color($success, $lightness: -60%)); }
   del { background-color: dark-light-choose($danger-low, scale-color($danger, $lightness: -60%)); }
   // Prevents users from breaking posts with tag nesting
-  big { font-size: 2rem; }
+  big { font-size: 1.5rem; }
   small { font-size: 0.75rem; }
   small small { font-size: .75em; }
   big big { font-size: 1em; }