diff --git a/buttons.less b/buttons.less
index ee6f6612a33b..0a484ead2d46 100644
--- a/buttons.less
+++ b/buttons.less
@@ -122,13 +122,12 @@
   // line-height: ensure even-numbered height of button next to large input
   .button-size(@padding-large-vertical; @padding-large-horizontal; @font-size-large; @line-height-large; @border-radius-large);
 }
-.btn-sm,
-.btn-xs {
+.btn-sm {
   // line-height: ensure proper height of button next to small input
   .button-size(@padding-small-vertical; @padding-small-horizontal; @font-size-small; @line-height-small; @border-radius-small);
 }
 .btn-xs {
-  padding: 1px 5px;
+  .button-size(@padding-xs-vertical; @padding-xs-horizontal; @font-size-small; @line-height-small; @border-radius-small);
 }
 
 
diff --git a/variables.less b/variables.less
index 120a65e063e3..1775be080d83 100644
--- a/variables.less
+++ b/variables.less
@@ -84,6 +84,9 @@
 @padding-small-vertical:         5px;
 @padding-small-horizontal:       10px;
 
+@padding-xs-vertical:            1px;
+@padding-xs-horizontal:          5px;
+
 @line-height-large:              1.33;
 @line-height-small:              1.5;