diff --git a/src/dat/controllers/NumberControllerBox.js b/src/dat/controllers/NumberControllerBox.js
index 462ebf25..7863b433 100644
--- a/src/dat/controllers/NumberControllerBox.js
+++ b/src/dat/controllers/NumberControllerBox.js
@@ -93,12 +93,30 @@ class NumberControllerBox extends NumberController {
     dom.bind(this.__input, 'blur', onBlur);
     dom.bind(this.__input, 'mousedown', onMouseDown);
     dom.bind(this.__input, 'keydown', function(e) {
-      // When pressing enter, you can be as precise as you want.
-      if (e.keyCode === 13) {
-        _this.__truncationSuspended = true;
-        this.blur();
-        _this.__truncationSuspended = false;
-        onFinish();
+      switch (e.key) {
+        case 'Enter':
+        {
+          // When pressing enter, you can be as precise as you want.
+          _this.__truncationSuspended = true;
+          this.blur();
+          _this.__truncationSuspended = false;
+          onFinish();
+          break;
+        }
+        case 'ArrowUp':
+        {
+          _this.setValue(_this.getValue() + _this.__impliedStep);
+          break;
+        }
+        case 'ArrowDown':
+        {
+          _this.setValue(_this.getValue() - _this.__impliedStep);
+          break;
+        }
+        default:
+        {
+          break;
+        }
       }
     });