diff --git a/ghost/admin/controllers/settings/general.js b/ghost/admin/controllers/settings/general.js
index 116f109840..33c0a89628 100644
--- a/ghost/admin/controllers/settings/general.js
+++ b/ghost/admin/controllers/settings/general.js
@@ -38,6 +38,12 @@ var SettingsGeneralController = Ember.ObjectController.extend({
                 self.notifications.showErrors(errors);
             });
         },
+
+        checkPostsPerPage: function () {
+            if (this.get('postsPerPage') < 1 || this.get('postsPerPage') > 1000 || isNaN(this.get('postsPerPage'))) {
+                this.set('postsPerPage', 5);
+            }
+        }
     }
 });
 
diff --git a/ghost/admin/templates/settings/general.hbs b/ghost/admin/templates/settings/general.hbs
index 23a23e242d..16dfbec03e 100644
--- a/ghost/admin/templates/settings/general.hbs
+++ b/ghost/admin/templates/settings/general.hbs
@@ -56,7 +56,7 @@
 
             <div class="form-group">
                 <label for="postsPerPage">Posts per page</label>
-                {{input id="postsPerPage" name="general[postsPerPage]" value=postsPerPage min="1" max="1000" type="number"}}
+                {{input id="postsPerPage" name="general[postsPerPage]" focus-out="checkPostsPerPage" value=postsPerPage min="1" max="1000" type="number"}}
                 <p>How many posts should be displayed on each page</p>
             </div>