diff --git a/core/utils/dom.js b/core/utils/dom.js
index 57843c8b9..5ec684acf 100644
--- a/core/utils/dom.js
+++ b/core/utils/dom.js
@@ -16,36 +16,37 @@
  * @name Blockly.utils.dom
  * @namespace
  */
-goog.provide('Blockly.utils.dom');
+goog.module('Blockly.utils.dom');
+goog.module.declareLegacyNamespace();
 
-goog.require('Blockly.utils.Svg');
-goog.require('Blockly.utils.userAgent');
+const Svg = goog.require('Blockly.utils.Svg');
+const userAgent = goog.require('Blockly.utils.userAgent');
 
 
 /**
  * Required name space for SVG elements.
  * @const
  */
-Blockly.utils.dom.SVG_NS = 'http://www.w3.org/2000/svg';
+const SVG_NS = 'http://www.w3.org/2000/svg';
 
 /**
  * Required name space for HTML elements.
  * @const
  */
-Blockly.utils.dom.HTML_NS = 'http://www.w3.org/1999/xhtml';
+const HTML_NS = 'http://www.w3.org/1999/xhtml';
 
 /**
  * Required name space for XLINK elements.
  * @const
  */
-Blockly.utils.dom.XLINK_NS = 'http://www.w3.org/1999/xlink';
+const XLINK_NS = 'http://www.w3.org/1999/xlink';
 
 /**
  * Node type constants.
  * https://developer.mozilla.org/en-US/docs/Web/API/Node/nodeType
  * @enum {number}
  */
-Blockly.utils.dom.NodeType = {
+const NodeType = {
   ELEMENT_NODE: 1,
   TEXT_NODE: 3,
   COMMENT_NODE: 8,
@@ -57,36 +58,35 @@ Blockly.utils.dom.NodeType = {
  * @type {Object}
  * @private
  */
-Blockly.utils.dom.cacheWidths_ = null;
+let cacheWidths = null;
 
 /**
  * Number of current references to cache.
  * @type {number}
  * @private
  */
-Blockly.utils.dom.cacheReference_ = 0;
+let cacheReference = 0;
 
 /**
  * A HTML canvas context used for computing text width.
  * @type {CanvasRenderingContext2D}
  * @private
  */
-Blockly.utils.dom.canvasContext_ = null;
+let canvasContext = null;
 
 /**
  * Helper method for creating SVG elements.
- * @param {string|Blockly.utils.Svg<T>} name Element's tag name.
+ * @param {string|Svg<T>} name Element's tag name.
  * @param {!Object} attrs Dictionary of attribute names and values.
  * @param {Element=} opt_parent Optional parent on which to append the element.
  * @return {T} Newly created SVG element.  The return type is {!SVGElement} if
- *     name is a string or a more specific type if it a member of
- *     Blockly.utils.Svg
+ *     name is a string or a more specific type if it a member of Svg.
  * @template T
  */
-Blockly.utils.dom.createSvgElement = function(name, attrs, opt_parent) {
-  var e = /** @type {T} */
-      (document.createElementNS(Blockly.utils.dom.SVG_NS, String(name)));
-  for (var key in attrs) {
+const createSvgElement = function(name, attrs, opt_parent) {
+  const e = /** @type {T} */
+      (document.createElementNS(SVG_NS, String(name)));
+  for (const key in attrs) {
     e.setAttribute(key, attrs[key]);
   }
   // IE defines a unique attribute "runtimeStyle", it is NOT applied to
@@ -108,8 +108,8 @@ Blockly.utils.dom.createSvgElement = function(name, attrs, opt_parent) {
  * @param {string} className Name of class to add.
  * @return {boolean} True if class was added, false if already present.
  */
-Blockly.utils.dom.addClass = function(element, className) {
-  var classes = element.getAttribute('class') || '';
+const addClass = function(element, className) {
+  let classes = element.getAttribute('class') || '';
   if ((' ' + classes + ' ').indexOf(' ' + className + ' ') != -1) {
     return false;
   }
@@ -126,11 +126,10 @@ Blockly.utils.dom.addClass = function(element, className) {
  * @param {string} classNames A string of one or multiple class names for an
  *    element.
  */
-Blockly.utils.dom.removeClasses = function(element, classNames) {
-  var classList = classNames.split(' ');
-  for (var i = 0; i < classList.length; i++) {
-    var cssName = classList[i];
-    Blockly.utils.dom.removeClass(element, cssName);
+const removeClasses = function(element, classNames) {
+  const classList = classNames.split(' ');
+  for (let i = 0; i < classList.length; i++) {
+    removeClass(element, classList[i]);
   }
 };
 
@@ -141,13 +140,13 @@ Blockly.utils.dom.removeClasses = function(element, classNames) {
  * @param {string} className Name of class to remove.
  * @return {boolean} True if class was removed, false if never present.
  */
-Blockly.utils.dom.removeClass = function(element, className) {
-  var classes = element.getAttribute('class');
+const removeClass = function(element, className) {
+  const classes = element.getAttribute('class');
   if ((' ' + classes + ' ').indexOf(' ' + className + ' ') == -1) {
     return false;
   }
-  var classList = classes.split(/\s+/);
-  for (var i = 0; i < classList.length; i++) {
+  const classList = classes.split(/\s+/);
+  for (let i = 0; i < classList.length; i++) {
     if (!classList[i] || classList[i] == className) {
       classList.splice(i, 1);
       i--;
@@ -168,8 +167,8 @@ Blockly.utils.dom.removeClass = function(element, className) {
  * @param {string} className Name of class to check.
  * @return {boolean} True if class exists, false otherwise.
  */
-Blockly.utils.dom.hasClass = function(element, className) {
-  var classes = element.getAttribute('class');
+const hasClass = function(element, className) {
+  const classes = element.getAttribute('class');
   return (' ' + classes + ' ').indexOf(' ' + className + ' ') != -1;
 };
 
@@ -179,7 +178,7 @@ Blockly.utils.dom.hasClass = function(element, className) {
  * @return {?Node} The node removed if removed; else, null.
  */
 // Copied from Closure goog.dom.removeNode
-Blockly.utils.dom.removeNode = function(node) {
+const removeNode = function(node) {
   return node && node.parentNode ? node.parentNode.removeChild(node) : null;
 };
 
@@ -189,9 +188,9 @@ Blockly.utils.dom.removeNode = function(node) {
  * @param {!Element} newNode New element to insert.
  * @param {!Element} refNode Existing element to precede new node.
  */
-Blockly.utils.dom.insertAfter = function(newNode, refNode) {
-  var siblingNode = refNode.nextSibling;
-  var parentNode = refNode.parentNode;
+const insertAfter = function(newNode, refNode) {
+  const siblingNode = refNode.nextSibling;
+  const parentNode = refNode.parentNode;
   if (!parentNode) {
     throw Error('Reference node has no parent.');
   }
@@ -208,9 +207,10 @@ Blockly.utils.dom.insertAfter = function(newNode, refNode) {
  * @param {!Node} descendant The node to test presence of.
  * @return {boolean} Whether the parent node contains the descendant node.
  */
-Blockly.utils.dom.containsNode = function(parent, descendant) {
-  return !!(parent.compareDocumentPosition(descendant) &
-            Blockly.utils.dom.NodeType.DOCUMENT_POSITION_CONTAINED_BY);
+const containsNode = function(parent, descendant) {
+  return !!(
+      parent.compareDocumentPosition(descendant) &
+      NodeType.DOCUMENT_POSITION_CONTAINED_BY);
 };
 
 /**
@@ -220,7 +220,7 @@ Blockly.utils.dom.containsNode = function(parent, descendant) {
  * @param {!Element} element Element to which the CSS transform will be applied.
  * @param {string} transform The value of the CSS `transform` property.
  */
-Blockly.utils.dom.setCssTransform = function(element, transform) {
+const setCssTransform = function(element, transform) {
   element.style['transform'] = transform;
   element.style['-webkit-transform'] = transform;
 };
@@ -229,10 +229,10 @@ Blockly.utils.dom.setCssTransform = function(element, transform) {
  * Start caching text widths. Every call to this function MUST also call
  * stopTextWidthCache. Caches must not survive between execution threads.
  */
-Blockly.utils.dom.startTextWidthCache = function() {
-  Blockly.utils.dom.cacheReference_++;
-  if (!Blockly.utils.dom.cacheWidths_) {
-    Blockly.utils.dom.cacheWidths_ = Object.create(null);
+const startTextWidthCache = function() {
+  cacheReference++;
+  if (!cacheWidths) {
+    cacheWidths = Object.create(null);
   }
 };
 
@@ -240,10 +240,10 @@ Blockly.utils.dom.startTextWidthCache = function() {
  * Stop caching field widths. Unless caching was already on when the
  * corresponding call to startTextWidthCache was made.
  */
-Blockly.utils.dom.stopTextWidthCache = function() {
-  Blockly.utils.dom.cacheReference_--;
-  if (!Blockly.utils.dom.cacheReference_) {
-    Blockly.utils.dom.cacheWidths_ = null;
+const stopTextWidthCache = function() {
+  cacheReference--;
+  if (!cacheReference) {
+    cacheWidths = null;
   }
 };
 
@@ -252,13 +252,13 @@ Blockly.utils.dom.stopTextWidthCache = function() {
  * @param {!Element} textElement An SVG 'text' element.
  * @return {number} Width of element.
  */
-Blockly.utils.dom.getTextWidth = function(textElement) {
-  var key = textElement.textContent + '\n' + textElement.className.baseVal;
-  var width;
+const getTextWidth = function(textElement) {
+  const key = textElement.textContent + '\n' + textElement.className.baseVal;
+  let width;
 
   // Return the cached width if it exists.
-  if (Blockly.utils.dom.cacheWidths_) {
-    width = Blockly.utils.dom.cacheWidths_[key];
+  if (cacheWidths) {
+    width = cacheWidths[key];
     if (width) {
       return width;
     }
@@ -266,7 +266,7 @@ Blockly.utils.dom.getTextWidth = function(textElement) {
 
   // Attempt to compute fetch the width of the SVG text element.
   try {
-    if (Blockly.utils.userAgent.IE || Blockly.utils.userAgent.EDGE) {
+    if (userAgent.IE || userAgent.EDGE) {
       width = textElement.getBBox().width;
     } else {
       width = textElement.getComputedTextLength();
@@ -280,8 +280,8 @@ Blockly.utils.dom.getTextWidth = function(textElement) {
   }
 
   // Cache the computed width and return.
-  if (Blockly.utils.dom.cacheWidths_) {
-    Blockly.utils.dom.cacheWidths_[key] = width;
+  if (cacheWidths) {
+    cacheWidths[key] = width;
   }
   return width;
 };
@@ -296,10 +296,10 @@ Blockly.utils.dom.getTextWidth = function(textElement) {
  * @param {string} fontFamily The font family to use.
  * @return {number} Width of element.
  */
-Blockly.utils.dom.getFastTextWidth = function(textElement,
-    fontSize, fontWeight, fontFamily) {
-  return Blockly.utils.dom.getFastTextWidthWithSizeString(textElement,
-      fontSize + 'pt', fontWeight, fontFamily);
+const getFastTextWidth = function(
+    textElement, fontSize, fontWeight, fontFamily) {
+  return getFastTextWidthWithSizeString(
+      textElement, fontSize + 'pt', fontWeight, fontFamily);
 };
 
 /**
@@ -314,41 +314,40 @@ Blockly.utils.dom.getFastTextWidth = function(textElement,
  * @param {string} fontFamily The font family to use.
  * @return {number} Width of element.
  */
-Blockly.utils.dom.getFastTextWidthWithSizeString = function(textElement,
-    fontSize, fontWeight, fontFamily) {
-  var text = textElement.textContent;
-  var key = text + '\n' + textElement.className.baseVal;
-  var width;
+const getFastTextWidthWithSizeString = function(
+    textElement, fontSize, fontWeight, fontFamily) {
+  const text = textElement.textContent;
+  const key = text + '\n' + textElement.className.baseVal;
+  let width;
 
   // Return the cached width if it exists.
-  if (Blockly.utils.dom.cacheWidths_) {
-    width = Blockly.utils.dom.cacheWidths_[key];
+  if (cacheWidths) {
+    width = cacheWidths[key];
     if (width) {
       return width;
     }
   }
 
-  if (!Blockly.utils.dom.canvasContext_) {
+  if (!canvasContext) {
     // Inject the canvas element used for computing text widths.
-    var computeCanvas = document.createElement('canvas');
+    const computeCanvas = document.createElement('canvas');
     computeCanvas.className = 'blocklyComputeCanvas';
     document.body.appendChild(computeCanvas);
 
     // Initialize the HTML canvas context and set the font.
     // The context font must match blocklyText's fontsize and font-family
     // set in CSS.
-    Blockly.utils.dom.canvasContext_ = computeCanvas.getContext('2d');
+    canvasContext = computeCanvas.getContext('2d');
   }
   // Set the desired font size and family.
-  Blockly.utils.dom.canvasContext_.font =
-      fontWeight + ' ' + fontSize + ' ' + fontFamily;
+  canvasContext.font = fontWeight + ' ' + fontSize + ' ' + fontFamily;
 
   // Measure the text width using the helper canvas context.
-  width = Blockly.utils.dom.canvasContext_.measureText(text).width;
+  width = canvasContext.measureText(text).width;
 
   // Cache the computed width and return.
-  if (Blockly.utils.dom.cacheWidths_) {
-    Blockly.utils.dom.cacheWidths_[key] = width;
+  if (cacheWidths) {
+    cacheWidths[key] = width;
   }
   return width;
 };
@@ -361,18 +360,16 @@ Blockly.utils.dom.getFastTextWidthWithSizeString = function(textElement,
  * @param {string} fontFamily The font family to use.
  * @return {{height: number, baseline: number}} Font measurements.
  */
-Blockly.utils.dom.measureFontMetrics = function(text, fontSize, fontWeight,
-    fontFamily) {
-
-  var span = document.createElement('span');
+const measureFontMetrics = function(text, fontSize, fontWeight, fontFamily) {
+  const span = document.createElement('span');
   span.style.font = fontWeight + ' ' + fontSize + ' ' + fontFamily;
   span.textContent = text;
 
-  var block = document.createElement('div');
+  const block = document.createElement('div');
   block.style.width = '1px';
   block.style.height = 0;
 
-  var div = document.createElement('div');
+  const div = document.createElement('div');
   div.setAttribute('style', 'position: fixed; top: 0; left: 0; display: flex;');
   div.appendChild(span);
   div.appendChild(block);
@@ -389,3 +386,25 @@ Blockly.utils.dom.measureFontMetrics = function(text, fontSize, fontWeight,
   }
   return result;
 };
+
+exports = {
+  SVG_NS,
+  HTML_NS,
+  XLINK_NS,
+  NodeType,
+  createSvgElement,
+  addClass,
+  removeClasses,
+  removeClass,
+  hasClass,
+  removeNode,
+  insertAfter,
+  containsNode,
+  setCssTransform,
+  startTextWidthCache,
+  stopTextWidthCache,
+  getTextWidth,
+  getFastTextWidth,
+  getFastTextWidthWithSizeString,
+  measureFontMetrics,
+};
diff --git a/tests/deps.js b/tests/deps.js
index 59f2bceee..20fb4e48e 100644
--- a/tests/deps.js
+++ b/tests/deps.js
@@ -179,7 +179,7 @@ goog.addDependency('../../core/utils/aria.js', ['Blockly.utils.aria'], []);
 goog.addDependency('../../core/utils/colour.js', ['Blockly.utils.colour'], [], {'lang': 'es6', 'module': 'goog'});
 goog.addDependency('../../core/utils/coordinate.js', ['Blockly.utils.Coordinate'], [], {'lang': 'es6', 'module': 'goog'});
 goog.addDependency('../../core/utils/deprecation.js', ['Blockly.utils.deprecation'], [], {'lang': 'es6', 'module': 'goog'});
-goog.addDependency('../../core/utils/dom.js', ['Blockly.utils.dom'], ['Blockly.utils.Svg', 'Blockly.utils.userAgent']);
+goog.addDependency('../../core/utils/dom.js', ['Blockly.utils.dom'], ['Blockly.utils.Svg', 'Blockly.utils.userAgent'], {'lang': 'es6', 'module': 'goog'});
 goog.addDependency('../../core/utils/global.js', ['Blockly.utils.global'], []);
 goog.addDependency('../../core/utils/idgenerator.js', ['Blockly.utils.IdGenerator'], [], {'lang': 'es6', 'module': 'goog'});
 goog.addDependency('../../core/utils/keycodes.js', ['Blockly.utils.KeyCodes'], [], {'lang': 'es6', 'module': 'goog'});