diff --git a/package-lock.json b/package-lock.json
index 401ed78e..da58db37 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "react-modal",
-  "version": "3.14.4",
+  "version": "3.15.1",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
@@ -1564,7 +1564,7 @@
     "array-from": {
       "version": "2.1.1",
       "resolved": "https://registry.npmjs.org/array-from/-/array-from-2.1.1.tgz",
-      "integrity": "sha1-z+nYwmYoudxa7MYqn12PHzUsEZU=",
+      "integrity": "sha512-GQTc6Uupx1FCavi5mPzBvVT7nEOeWMmUA9P95wpfpW1XwMSKs+KaymD5C2Up7KAUKg/mYwbsUYzdZWcoajlNZg==",
       "dev": true
     },
     "array-includes": {
diff --git a/specs/helper.js b/specs/helper.js
index 9ff09c84..fee49570 100644
--- a/specs/helper.js
+++ b/specs/helper.js
@@ -182,7 +182,7 @@ const dispatchMockEvent = eventCtor => (key, code) => (element, opts) =>
       {},
       {
         key: key,
-        keyCode: code,
+        code: code,
         which: code
       },
       opts
@@ -194,11 +194,11 @@ const dispatchMockKeyDownEvent = dispatchMockEvent(Simulate.keyDown);
 /**
  * Dispatch an 'esc' key down event from an element.
  */
-export const escKeyDown = dispatchMockKeyDownEvent("ESC", 27);
+export const escKeyDown = dispatchMockKeyDownEvent("ESC", "Escape");
 /**
  * Dispatch a 'tab' key down event from an element.
  */
-export const tabKeyDown = dispatchMockKeyDownEvent("TAB", 9);
+export const tabKeyDown = dispatchMockKeyDownEvent("TAB", "Tab");
 /**
  * Dispatch a 'click' event at a node.
  */
diff --git a/src/components/ModalPortal.js b/src/components/ModalPortal.js
index 8f673af1..867f756f 100644
--- a/src/components/ModalPortal.js
+++ b/src/components/ModalPortal.js
@@ -17,9 +17,6 @@ const CLASS_NAMES = {
   content: "ReactModal__Content"
 };
 
-const TAB_KEY = 9;
-const ESC_KEY = 27;
-
 let ariaHiddenInstances = 0;
 
 export default class ModalPortal extends Component {
@@ -284,11 +281,11 @@ export default class ModalPortal extends Component {
   };
 
   handleKeyDown = event => {
-    if (event.keyCode === TAB_KEY) {
+    if (event.code === "Tab") {
       scopeTab(this.content, event);
     }
 
-    if (this.props.shouldCloseOnEsc && event.keyCode === ESC_KEY) {
+    if (this.props.shouldCloseOnEsc && event.code === "Escape") {
       event.stopPropagation();
       this.requestClose(event);
     }