diff --git a/src/css.js b/src/css.js
index acd4bb3eb..5d3a0a6b5 100644
--- a/src/css.js
+++ b/src/css.js
@@ -190,6 +190,7 @@ jQuery.extend( {
 
 	// Don't automatically add "px" to these possibly-unitless properties
 	cssNumber: {
+		"animationIterationCount": true,
 		"columnCount": true,
 		"fillOpacity": true,
 		"flexGrow": true,
diff --git a/test/unit/css.js b/test/unit/css.js
index 8715c56d5..4b4017ab8 100644
--- a/test/unit/css.js
+++ b/test/unit/css.js
@@ -840,26 +840,35 @@ if ( jQuery.fn.offset ) {
 	} );
 }
 
-QUnit.test( "Do not append px (#9548, #12990)", function( assert ) {
-	assert.expect( 2 );
+QUnit.test( "Do not append px (#9548, #12990, #2792)", function( assert ) {
+	assert.expect( 3 );
 
 	var $div = jQuery( "<div>" ).appendTo( "#qunit-fixture" );
 
 	$div.css( "fill-opacity", 1 );
 
 	// Support: Android 2.3 (no support for fill-opacity)
-	if ( $div.css( "fill-opacity" ) ) {
+	if ( $div.css( "fill-opacity" ) !== undefined ) {
 		assert.equal( $div.css( "fill-opacity" ), 1, "Do not append px to 'fill-opacity'" );
 	} else {
 		assert.ok( true, "No support for fill-opacity CSS property" );
 	}
 
 	$div.css( "column-count", 1 );
-	if ( $div.css( "column-count" ) ) {
+	if ( $div.css( "column-count" ) !== undefined ) {
 		assert.equal( $div.css( "column-count" ), 1, "Do not append px to 'column-count'" );
 	} else {
 		assert.ok( true, "No support for column-count CSS property" );
 	}
+
+	$div.css( "animation-iteration-count", 2 );
+	if ( $div.css( "animation-iteration-count" ) !== undefined ) {
+		// if $div.css( "animation-iteration-count" ) return "1",
+		// it actually return the default value of animation-iteration-count
+		assert.equal( $div.css( "animation-iteration-count" ), 2, "Do not append px to 'animation-iteration-count'" );
+	} else {
+		assert.ok( true, "No support for animation-iteration-count CSS property" );
+	}
 } );
 
 QUnit.test( "css('width') and css('height') should respect box-sizing, see #11004", function( assert ) {