diff --git a/less/modals.less b/less/modals.less
index 776073d572..c44b760944 100644
--- a/less/modals.less
+++ b/less/modals.less
@@ -123,6 +123,14 @@
     width: 600px;
     padding-top: 30px;
     padding-bottom: 30px;
+    // Define large size for the modal
+    &.modal-lg{
+      width: @modal-lg;
+    }
+    // Define small size for the modal
+    &.modal-sm{
+      width: @modal-sm;
+    }
   }
   .modal-content {
     .box-shadow(0 5px 15px rgba(0,0,0,.5));
diff --git a/less/variables.less b/less/variables.less
index e596215d06..5fb66b2254 100644
--- a/less/variables.less
+++ b/less/variables.less
@@ -448,6 +448,9 @@
 @modal-header-border-color:   #e5e5e5;
 @modal-footer-border-color:   @modal-header-border-color;
 
+@modal-lg:                    900px;
+@modal-sm:                    400px;
+
 
 // Alerts
 // -------------------------