diff --git a/app/assets/javascripts/posts.js b/app/assets/javascripts/posts.js
index a236cb4f2..998c2c7cd 100644
--- a/app/assets/javascripts/posts.js
+++ b/app/assets/javascripts/posts.js
@@ -51,17 +51,26 @@
         return false;
       },
       select: function(event, ui) {
-        this.value = this.value.replace(/\S+\s*$/g, ui.item.value + " ");
+        var before_caret_text = this.value.substring(0, this.selectionStart);
+        var after_caret_text = this.value.substring(this.selectionStart);
+
+        this.value = before_caret_text.replace(/\S+\s*$/g, ui.item.value + " ");
+
+        // Preserve original caret position to prevent it from jumping to the end
+        var original_start = this.selectionStart;
+        this.value += after_caret_text;
+        this.selectionStart = this.selectionEnd = original_start;
+
         return false;
       },
       source: function(req, resp) {
-        var pre_caret_text = req.term.substring(0, this.element.get(0).selectionStart);
+        var before_caret_text = req.term.substring(0, this.element.get(0).selectionStart);
 
-        if (pre_caret_text.match(/ $/)) {
+        if (before_caret_text.match(/ $/)) {
           return;
         }
 
-        var term = pre_caret_text.match(/\S+/g).pop();
+        var term = before_caret_text.match(/\S+/g).pop();
         $.ajax({
           url: "/tags.json",
           data: {