diff --git a/docs/examples/en/loaders/BasisTextureLoader.html b/docs/examples/en/loaders/BasisTextureLoader.html
index a986252938702b..22109d3cf45a06 100644
--- a/docs/examples/en/loaders/BasisTextureLoader.html
+++ b/docs/examples/en/loaders/BasisTextureLoader.html
@@ -64,10 +64,6 @@ <h2>Browser compatibility</h2>
 		<p>
 			Transcoding to PVRTC1 (for iOS) requires square power-of-two textures.
 		</p>
-		<p>
-			This loader relies on ES6 Promises and Web Assembly, which are not
-			supported in IE11.
-		</p>
 
 		<br>
 		<hr>
diff --git a/docs/examples/en/loaders/DRACOLoader.html b/docs/examples/en/loaders/DRACOLoader.html
index a84a6488eabf13..25906e7f8a661c 100644
--- a/docs/examples/en/loaders/DRACOLoader.html
+++ b/docs/examples/en/loaders/DRACOLoader.html
@@ -70,12 +70,9 @@ <h2>Example</h2>
 
 		<h2>Browser compatibility</h2>
 
-		<p>DRACOLoader relies on ES6 [link:https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise Promises],
-		which are not supported in IE11. To use the loader in IE11, you must
-		[link:https://github.com/stefanpenner/es6-promise include a polyfill]
-		providing a Promise replacement. DRACOLoader will automatically use
-		either the JS or the WASM decoding library, based on browser
-		capabilities.</p>
+		<p>
+			DRACOLoader will automatically use either the JS or the WASM decoding library, based on browser capabilities.
+		</p>
 
 		<br>
 		<hr>
diff --git a/docs/examples/en/loaders/GLTFLoader.html b/docs/examples/en/loaders/GLTFLoader.html
index c8b09458924eed..b56263f88eae0d 100644
--- a/docs/examples/en/loaders/GLTFLoader.html
+++ b/docs/examples/en/loaders/GLTFLoader.html
@@ -95,13 +95,6 @@ <h2>Example</h2>
 
 		[example:webgl_loader_gltf]
 
-		<h2>Browser compatibility</h2>
-
-		<p>GLTFLoader relies on ES6 [link:https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise Promises],
-		which are not supported in IE11. To use the loader in IE11, you must
-		[link:https://github.com/stefanpenner/es6-promise include a polyfill]
-		providing a Promise replacement.</p>
-
 		<h2>Textures</h2>
 
 		<p>Textures containing color information (.map, .emissiveMap, and .specularMap) always use sRGB colorspace in
diff --git a/docs/examples/zh/loaders/BasisTextureLoader.html b/docs/examples/zh/loaders/BasisTextureLoader.html
index a986252938702b..22109d3cf45a06 100644
--- a/docs/examples/zh/loaders/BasisTextureLoader.html
+++ b/docs/examples/zh/loaders/BasisTextureLoader.html
@@ -64,10 +64,6 @@ <h2>Browser compatibility</h2>
 		<p>
 			Transcoding to PVRTC1 (for iOS) requires square power-of-two textures.
 		</p>
-		<p>
-			This loader relies on ES6 Promises and Web Assembly, which are not
-			supported in IE11.
-		</p>
 
 		<br>
 		<hr>
diff --git a/docs/examples/zh/loaders/DRACOLoader.html b/docs/examples/zh/loaders/DRACOLoader.html
index a84a6488eabf13..25906e7f8a661c 100644
--- a/docs/examples/zh/loaders/DRACOLoader.html
+++ b/docs/examples/zh/loaders/DRACOLoader.html
@@ -70,12 +70,9 @@ <h2>Example</h2>
 
 		<h2>Browser compatibility</h2>
 
-		<p>DRACOLoader relies on ES6 [link:https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise Promises],
-		which are not supported in IE11. To use the loader in IE11, you must
-		[link:https://github.com/stefanpenner/es6-promise include a polyfill]
-		providing a Promise replacement. DRACOLoader will automatically use
-		either the JS or the WASM decoding library, based on browser
-		capabilities.</p>
+		<p>
+			DRACOLoader will automatically use either the JS or the WASM decoding library, based on browser capabilities.
+		</p>
 
 		<br>
 		<hr>
diff --git a/docs/examples/zh/loaders/GLTFLoader.html b/docs/examples/zh/loaders/GLTFLoader.html
index 925437751bd4a9..5d1078130d8c72 100644
--- a/docs/examples/zh/loaders/GLTFLoader.html
+++ b/docs/examples/zh/loaders/GLTFLoader.html
@@ -94,12 +94,6 @@ <h2>示例</h2>
 
 		[example:webgl_loader_gltf]
 
-		<h2>浏览器兼容性</h2>
-
-		<p>GLTFLoader 依赖 ES6 [link:https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise Promises]，
-		这一特性不支持IE11。若要在IE11中使用该加载器，你必须引入polyfill（[link:https://github.com/stefanpenner/es6-promise include a polyfill]）
-		来提供一个Promise的替代方案。</p>
-
 		<h2>纹理</h2>
 
 		<p>纹理中包含的颜色信息（.map, .emissiveMap, 和 .specularMap）在glTF中总是使用sRGB颜色空间，而顶点颜色和材质属性（.color, .emissive, .specular）
diff --git a/docs/manual/en/introduction/Browser-support.html b/docs/manual/en/introduction/Browser-support.html
index ea51237b4a488f..c7119abb3a62ab 100644
--- a/docs/manual/en/introduction/Browser-support.html
+++ b/docs/manual/en/introduction/Browser-support.html
@@ -13,17 +13,14 @@ <h1>[name]</h1>
 	<h2>Overview</h2>
 	<div>
 		<p>
-			Three.js can use WebGL to render your scenes on all modern browsers. For older browsers, especially Internet Explorer 10 and below, you may have to fallback to one of the other [link:https://github.com/mrdoob/three.js/tree/master/examples/js/renderers renderers] (CSS2DRenderer, CSS3DRenderer, SVGRenderer). Additionally, you may have to include some polyfills, especially if you are using files from the [link:https://github.com/mrdoob/three.js/tree/master/examples /examples] folder.
-		</p>
-		<p>
-			Note: if you don't need to support these old browsers, then it is not recommended to use the other renderers as they are slower and support less features than the WebGLRenderer.
+			Three.js can use WebGL to render your scenes on all modern browsers. Additionally, you may have to include some polyfills, especially if you are using files from the [link:https://github.com/mrdoob/three.js/tree/master/examples /examples] folder.
 		</p>
 	</div>
 
 	<h2>Browsers that support WebGL</h2>
 	<div>
 		<p>
-			Google Chrome 9+, Firefox 4+, Opera 15+, Safari 5.1+, Internet Explorer 11 and Microsoft Edge. You can find which browsers support WebGL at [link:https://caniuse.com/#feat=webgl Can I use WebGL].
+			Google Chrome 9+, Firefox 4+, Opera 15+, Safari 5.1+ and Microsoft Edge. You can find which browsers support WebGL at [link:https://caniuse.com/#feat=webgl Can I use WebGL].
 		</p>
 	</div>
 
@@ -91,15 +88,6 @@ <h2>JavaScript Language Features or Web APIs Used in three.js</h2>
 	</div>
 
 	<h2>Polyfills</h2>
-	<div>
-		<p>Just import polyfills based on your requirements. Taking IE9 as an example, you need to polyfill at least these features:</p>
-		<ul>
-			<li>Typed Arrays</li>
-			<li>Blob</li>
-		</ul>
-	</div>
-
-	<h3>Suggested polyfills</h3>
 	<div>
 		<ul>
 			<li>
diff --git a/docs/manual/zh/introduction/Browser-support.html b/docs/manual/zh/introduction/Browser-support.html
index dba7cbf7041c36..13c4c7c79d54e6 100644
--- a/docs/manual/zh/introduction/Browser-support.html
+++ b/docs/manual/zh/introduction/Browser-support.html
@@ -13,17 +13,14 @@ <h1>浏览器支持（[name]）</h1>
 	<h2>总览</h2>
 	<div>
 		<p>
-            在所有现代浏览器中，Three.js可以使用WebGL来渲染场景。对于较旧的浏览器，特别是Internet Explorer 10或者更低版本浏览器，你将需要回落到其它[link:https://github.com/mrdoob/three.js/tree/master/examples/js/renderers renderers]（CSS2DRenderer、CSS3DRenderer、SVGRenderer）。此外，你或许不得不包含一些额外的“填充物”来解决兼容性问题，特别是当你使用[link:https://github.com/mrdoob/three.js/tree/master/examples /examples]目录中的文件时。
-		</p>
-		<p>
-            注意：如果你并不需要支持较旧的浏览器，那就不推荐使用其他渲染器来进行渲染，因为与WebGLRenderer相比，其它渲染器渲染较慢，并且不支持WebGL的诸多特性。
+            在所有现代浏览器中，Three.js可以使用WebGL来渲染场景。此外，你或许不得不包含一些额外的“填充物”来解决兼容性问题，特别是当你使用[link:https://github.com/mrdoob/three.js/tree/master/examples /examples]目录中的文件时。
 		</p>
 	</div>
 
 	<h2>支持WebGL的浏览器</h2>
 	<div>
 		<p>
-			Google Chrome 9+、Firefox 4+、Opera 15+、Safari 5.1+、Internet Explorer 11 和 Microsoft Edge。你可以点击[link:https://caniuse.com/#feat=webgl Can I use WebGL]来查阅各个浏览器对WebGL的支持性。
+			Google Chrome 9+、Firefox 4+、Opera 15+、Safari 5.1+ 和 Microsoft Edge。你可以点击[link:https://caniuse.com/#feat=webgl Can I use WebGL]来查阅各个浏览器对WebGL的支持性。
 		</p>
 	</div>
 
@@ -93,15 +90,6 @@ <h2>
 	</div>
 
 	<h2>关于用于解决兼容性问题的“填充物”</h2>
-	<div>
-		<p>根据你的需求，引入相关的“填充物”即可。以IE9为例，你至少需要来使用“填充物”完成以下的功能。</p>
-		<ul>
-			<li>Typed Arrays</li>
-			<li>Blob</li>
-		</ul>
-	</div>
-
-	<h3>建议的“填充物”</h3>
 	<div>
 		<ul>
 			<li>
diff --git a/examples/js/renderers/CSS3DRenderer.js b/examples/js/renderers/CSS3DRenderer.js
index c48888038ca2a0..e810b57b89a631 100644
--- a/examples/js/renderers/CSS3DRenderer.js
+++ b/examples/js/renderers/CSS3DRenderer.js
@@ -65,8 +65,6 @@ THREE.CSS3DRenderer = function () {
 
 	domElement.appendChild( cameraElement );
 
-	var isIE = /Trident/i.test( navigator.userAgent );
-
 	this.getSize = function () {
 
 		return {
@@ -122,7 +120,7 @@ THREE.CSS3DRenderer = function () {
 
 	}
 
-	function getObjectCSSMatrix( matrix, cameraCSSMatrix ) {
+	function getObjectCSSMatrix( matrix ) {
 
 		var elements = matrix.elements;
 		var matrix3d = 'matrix3d(' +
@@ -144,15 +142,6 @@ THREE.CSS3DRenderer = function () {
 			epsilon( elements[ 15 ] ) +
 		')';
 
-		if ( isIE ) {
-
-			return 'translate(-50%,-50%)' +
-				'translate(' + _widthHalf + 'px,' + _heightHalf + 'px)' +
-				cameraCSSMatrix +
-				matrix3d;
-
-		}
-
 		return 'translate(-50%,-50%)' + matrix3d;
 
 	}
@@ -177,11 +166,11 @@ THREE.CSS3DRenderer = function () {
 				matrix.elements[ 11 ] = 0;
 				matrix.elements[ 15 ] = 1;
 
-				style = getObjectCSSMatrix( matrix, cameraCSSMatrix );
+				style = getObjectCSSMatrix( matrix );
 
 			} else {
 
-				style = getObjectCSSMatrix( object.matrixWorld, cameraCSSMatrix );
+				style = getObjectCSSMatrix( object.matrixWorld );
 
 			}
 
@@ -195,12 +184,6 @@ THREE.CSS3DRenderer = function () {
 
 				var objectData = { style: style };
 
-				if ( isIE ) {
-
-					objectData.distanceToCameraSquared = getDistanceToSquared( camera, object );
-
-				}
-
 				cache.objects.set( object, objectData );
 
 			}
@@ -221,57 +204,6 @@ THREE.CSS3DRenderer = function () {
 
 	}
 
-	var getDistanceToSquared = function () {
-
-		var a = new THREE.Vector3();
-		var b = new THREE.Vector3();
-
-		return function ( object1, object2 ) {
-
-			a.setFromMatrixPosition( object1.matrixWorld );
-			b.setFromMatrixPosition( object2.matrixWorld );
-
-			return a.distanceToSquared( b );
-
-		};
-
-	}();
-
-	function filterAndFlatten( scene ) {
-
-		var result = [];
-
-		scene.traverse( function ( object ) {
-
-			if ( object instanceof THREE.CSS3DObject ) result.push( object );
-
-		} );
-
-		return result;
-
-	}
-
-	function zOrder( scene ) {
-
-		var sorted = filterAndFlatten( scene ).sort( function ( a, b ) {
-
-			var distanceA = cache.objects.get( a ).distanceToCameraSquared;
-			var distanceB = cache.objects.get( b ).distanceToCameraSquared;
-
-			return distanceA - distanceB;
-
-		} );
-
-		var zMax = sorted.length;
-
-		for ( var i = 0, l = sorted.length; i < l; i ++ ) {
-
-			sorted[ i ].element.style.zIndex = zMax - i;
-
-		}
-
-	}
-
 	this.render = function ( scene, camera ) {
 
 		var fov = camera.projectionMatrix.elements[ 5 ] * _heightHalf;
@@ -312,7 +244,7 @@ THREE.CSS3DRenderer = function () {
 		var style = cameraCSSMatrix +
 			'translate(' + _widthHalf + 'px,' + _heightHalf + 'px)';
 
-		if ( cache.camera.style !== style && ! isIE ) {
+		if ( cache.camera.style !== style ) {
 
 			cameraElement.style.WebkitTransform = style;
 			cameraElement.style.transform = style;
@@ -323,16 +255,6 @@ THREE.CSS3DRenderer = function () {
 
 		renderObject( scene, camera, cameraCSSMatrix );
 
-		if ( isIE ) {
-
-			// IE10 and 11 does not support 'preserve-3d'.
-			// Thus, z-order in 3D will not work.
-			// We have to calc z-order manually and set CSS z-index for IE.
-			// FYI: z-index can't handle object intersection
-			zOrder( scene );
-
-		}
-
 	};
 
 };
diff --git a/examples/jsm/renderers/CSS3DRenderer.js b/examples/jsm/renderers/CSS3DRenderer.js
index c0baf52eac7cc3..a8ec8509d044f1 100644
--- a/examples/jsm/renderers/CSS3DRenderer.js
+++ b/examples/jsm/renderers/CSS3DRenderer.js
@@ -6,8 +6,7 @@
 
 import {
 	Matrix4,
-	Object3D,
-	Vector3
+	Object3D
 } from "../../../build/three.module.js";
 
 var CSS3DObject = function ( element ) {
@@ -71,8 +70,6 @@ var CSS3DRenderer = function () {
 
 	domElement.appendChild( cameraElement );
 
-	var isIE = /Trident/i.test( navigator.userAgent );
-
 	this.getSize = function () {
 
 		return {
@@ -128,7 +125,7 @@ var CSS3DRenderer = function () {
 
 	}
 
-	function getObjectCSSMatrix( matrix, cameraCSSMatrix ) {
+	function getObjectCSSMatrix( matrix ) {
 
 		var elements = matrix.elements;
 		var matrix3d = 'matrix3d(' +
@@ -150,15 +147,6 @@ var CSS3DRenderer = function () {
 			epsilon( elements[ 15 ] ) +
 		')';
 
-		if ( isIE ) {
-
-			return 'translate(-50%,-50%)' +
-				'translate(' + _widthHalf + 'px,' + _heightHalf + 'px)' +
-				cameraCSSMatrix +
-				matrix3d;
-
-		}
-
 		return 'translate(-50%,-50%)' + matrix3d;
 
 	}
@@ -183,11 +171,11 @@ var CSS3DRenderer = function () {
 				matrix.elements[ 11 ] = 0;
 				matrix.elements[ 15 ] = 1;
 
-				style = getObjectCSSMatrix( matrix, cameraCSSMatrix );
+				style = getObjectCSSMatrix( matrix );
 
 			} else {
 
-				style = getObjectCSSMatrix( object.matrixWorld, cameraCSSMatrix );
+				style = getObjectCSSMatrix( object.matrixWorld );
 
 			}
 
@@ -201,12 +189,6 @@ var CSS3DRenderer = function () {
 
 				var objectData = { style: style };
 
-				if ( isIE ) {
-
-					objectData.distanceToCameraSquared = getDistanceToSquared( camera, object );
-
-				}
-
 				cache.objects.set( object, objectData );
 
 			}
@@ -227,57 +209,6 @@ var CSS3DRenderer = function () {
 
 	}
 
-	var getDistanceToSquared = function () {
-
-		var a = new Vector3();
-		var b = new Vector3();
-
-		return function ( object1, object2 ) {
-
-			a.setFromMatrixPosition( object1.matrixWorld );
-			b.setFromMatrixPosition( object2.matrixWorld );
-
-			return a.distanceToSquared( b );
-
-		};
-
-	}();
-
-	function filterAndFlatten( scene ) {
-
-		var result = [];
-
-		scene.traverse( function ( object ) {
-
-			if ( object instanceof CSS3DObject ) result.push( object );
-
-		} );
-
-		return result;
-
-	}
-
-	function zOrder( scene ) {
-
-		var sorted = filterAndFlatten( scene ).sort( function ( a, b ) {
-
-			var distanceA = cache.objects.get( a ).distanceToCameraSquared;
-			var distanceB = cache.objects.get( b ).distanceToCameraSquared;
-
-			return distanceA - distanceB;
-
-		} );
-
-		var zMax = sorted.length;
-
-		for ( var i = 0, l = sorted.length; i < l; i ++ ) {
-
-			sorted[ i ].element.style.zIndex = zMax - i;
-
-		}
-
-	}
-
 	this.render = function ( scene, camera ) {
 
 		var fov = camera.projectionMatrix.elements[ 5 ] * _heightHalf;
@@ -318,7 +249,7 @@ var CSS3DRenderer = function () {
 		var style = cameraCSSMatrix +
 			'translate(' + _widthHalf + 'px,' + _heightHalf + 'px)';
 
-		if ( cache.camera.style !== style && ! isIE ) {
+		if ( cache.camera.style !== style ) {
 
 			cameraElement.style.WebkitTransform = style;
 			cameraElement.style.transform = style;
@@ -329,16 +260,6 @@ var CSS3DRenderer = function () {
 
 		renderObject( scene, camera, cameraCSSMatrix );
 
-		if ( isIE ) {
-
-			// IE10 and 11 does not support 'preserve-3d'.
-			// Thus, z-order in 3D will not work.
-			// We have to calc z-order manually and set CSS z-index for IE.
-			// FYI: z-index can't handle object intersection
-			zOrder( scene );
-
-		}
-
 	};
 
 };
diff --git a/src/loaders/BufferGeometryLoader.js b/src/loaders/BufferGeometryLoader.js
index 45107f9d4f3fed..30b7a782549367 100644
--- a/src/loaders/BufferGeometryLoader.js
+++ b/src/loaders/BufferGeometryLoader.js
@@ -138,8 +138,7 @@ BufferGeometryLoader.prototype = Object.assign( Object.create( Loader.prototype
 var TYPED_ARRAYS = {
 	Int8Array: Int8Array,
 	Uint8Array: Uint8Array,
-	// Workaround for IE11 pre KB2929437. See #11440
-	Uint8ClampedArray: typeof Uint8ClampedArray !== 'undefined' ? Uint8ClampedArray : Uint8Array,
+	Uint8ClampedArray: Uint8ClampedArray,
 	Int16Array: Int16Array,
 	Uint16Array: Uint16Array,
 	Int32Array: Int32Array,
diff --git a/src/renderers/WebGLRenderer.js b/src/renderers/WebGLRenderer.js
index aa5be56db86154..afc098028fb9a3 100644
--- a/src/renderers/WebGLRenderer.js
+++ b/src/renderers/WebGLRenderer.js
@@ -2713,7 +2713,7 @@ function WebGLRenderer( parameters ) {
 
 				}
 
-				if ( textureType !== UnsignedByteType && utils.convert( textureType ) !== _gl.getParameter( _gl.IMPLEMENTATION_COLOR_READ_TYPE ) && // IE11, Edge and Chrome Mac < 52 (#9513)
+				if ( textureType !== UnsignedByteType && utils.convert( textureType ) !== _gl.getParameter( _gl.IMPLEMENTATION_COLOR_READ_TYPE ) && // Edge and Chrome Mac < 52 (#9513)
 					! ( textureType === FloatType && ( capabilities.isWebGL2 || extensions.get( 'OES_texture_float' ) || extensions.get( 'WEBGL_color_buffer_float' ) ) ) && // Chrome Mac >= 52 and Firefox
 					! ( textureType === HalfFloatType && ( capabilities.isWebGL2 ? extensions.get( 'EXT_color_buffer_float' ) : extensions.get( 'EXT_color_buffer_half_float' ) ) ) ) {
 
diff --git a/src/renderers/webgl/WebGLTextures.js b/src/renderers/webgl/WebGLTextures.js
index 89e1e182d63cf7..c3495c451874b7 100644
--- a/src/renderers/webgl/WebGLTextures.js
+++ b/src/renderers/webgl/WebGLTextures.js
@@ -132,8 +132,7 @@ function WebGLTextures( _gl, extensions, state, properties, capabilities, utils,
 
 		var textureProperties = properties.get( texture );
 
-		// Note: Math.log( x ) * Math.LOG2E used instead of Math.log2( x ) which is not supported by IE11
-		textureProperties.__maxMipLevel = Math.log( Math.max( width, height ) ) * Math.LOG2E;
+		textureProperties.__maxMipLevel = Math.log2( Math.max( width, height ) );
 
 	}