diff --git a/frontend_tests/node_tests/drafts.js b/frontend_tests/node_tests/drafts.js
index 7429e71c06..49e0c92ff0 100644
--- a/frontend_tests/node_tests/drafts.js
+++ b/frontend_tests/node_tests/drafts.js
@@ -54,7 +54,7 @@ function stub_timestamp(timestamp, func) {
     function fake_time() {
         return timestamp;
     }
-    with_field(Date.prototype, "getTime", fake_time, func);
+    with_field(Date, "now", fake_time, func);
 }
 
 const legacy_draft = {
diff --git a/static/js/debug.js b/static/js/debug.js
index 086a94af9a..94b7b8bcc1 100644
--- a/static/js/debug.js
+++ b/static/js/debug.js
@@ -11,9 +11,9 @@
     to the console along with the name "foo". */
 
 export function print_elapsed_time(name, fun) {
-    const t0 = new Date().getTime();
+    const t0 = Date.now();
     const out = fun();
-    const t1 = new Date().getTime();
+    const t1 = Date.now();
     console.log(name + ": " + (t1 - t0) + " ms");
     return out;
 }
diff --git a/static/js/drafts.js b/static/js/drafts.js
index 1cffbabbd7..9b1ac59721 100644
--- a/static/js/drafts.js
+++ b/static/js/drafts.js
@@ -23,7 +23,7 @@ const draft_model = (function () {
     ls.version = 1;
 
     function getTimestamp() {
-        return new Date().getTime();
+        return Date.now();
     }
 
     function get() {
diff --git a/static/js/feedback_widget.js b/static/js/feedback_widget.js
index 7527138013..7601939d22 100644
--- a/static/js/feedback_widget.js
+++ b/static/js/feedback_widget.js
@@ -33,7 +33,7 @@ const animate = {
             return;
         }
 
-        if (meta.hide_me_time < new Date().getTime() && !meta.alert_hover_state) {
+        if (meta.hide_me_time < Date.now() && !meta.alert_hover_state) {
             animate.fadeOut();
             return;
         }
@@ -89,7 +89,7 @@ function set_up_handlers() {
         meta.alert_hover_state = false;
         // add at least 2000ms but if more than that exists just keep the
         // current amount.
-        meta.hide_me_time = Math.max(meta.hide_me_time, new Date().getTime() + 2000);
+        meta.hide_me_time = Math.max(meta.hide_me_time, Date.now() + 2000);
     });
 
     meta.$container.on("click", ".exit-me", () => {
@@ -128,7 +128,7 @@ exports.show = function (opts) {
     meta.undo = opts.on_undo;
 
     // add a four second delay before closing up.
-    meta.hide_me_time = new Date().getTime() + 4000;
+    meta.hide_me_time = Date.now() + 4000;
 
     meta.$container.find(".feedback_title").text(opts.title_text);
     meta.$container.find(".feedback_undo").text(opts.undo_button_text);
diff --git a/static/js/localstorage.js b/static/js/localstorage.js
index 188d5b5350..c2462b74a4 100644
--- a/static/js/localstorage.js
+++ b/static/js/localstorage.js
@@ -26,7 +26,7 @@ const ls = {
         return {
             data,
             __valid: true,
-            expires: new Date().getTime() + expires,
+            expires: Date.now() + expires,
         };
     },
 
diff --git a/static/js/message_edit.js b/static/js/message_edit.js
index 23fd915e8c..494a6b9977 100644
--- a/static/js/message_edit.js
+++ b/static/js/message_edit.js
@@ -758,7 +758,7 @@ exports.save_message_row_edit = function (row) {
         // Settings these attributes causes a "SAVING" notice to
         // briefly appear where "EDITED" would normally appear until
         // the message is acknowledged by the server.
-        message.local_edit_timestamp = Math.round(new Date().getTime() / 1000);
+        message.local_edit_timestamp = Math.round(Date.now() / 1000);
 
         echo.edit_locally(message, currently_echoing_messages.get(message_id));
 
diff --git a/static/js/muting_ui.js b/static/js/muting_ui.js
index d79362f3a0..52f2b2c615 100644
--- a/static/js/muting_ui.js
+++ b/static/js/muting_ui.js
@@ -4,7 +4,7 @@ const render_muted_topic_ui_row = require("../templates/muted_topic_ui_row.hbs")
 const render_topic_muted = require("../templates/topic_muted.hbs");
 
 function timestamp_ms() {
-    return new Date().getTime();
+    return Date.now();
 }
 
 let last_topic_update = 0;
diff --git a/static/js/popovers.js b/static/js/popovers.js
index 874c048f73..07b5b1a700 100644
--- a/static/js/popovers.js
+++ b/static/js/popovers.js
@@ -1260,7 +1260,7 @@ exports.register_click_handlers = function () {
                 return;
             }
 
-            const date = new Date().getTime();
+            const date = Date.now();
 
             // only run `popovers.hide_all()` if the last scroll was more
             // than 250ms ago.
diff --git a/static/js/setup.js b/static/js/setup.js
index fdc9884daf..218b28c6bc 100644
--- a/static/js/setup.js
+++ b/static/js/setup.js
@@ -15,7 +15,7 @@ $(() => {
         page_params.needs_tutorial = false;
     }
 
-    page_params.page_load_time = new Date().getTime();
+    page_params.page_load_time = Date.now();
 
     // Display loading indicator.  This disappears after the first
     // get_events completes.
diff --git a/static/js/typing.js b/static/js/typing.js
index d7e7bc35d9..830442dc8b 100644
--- a/static/js/typing.js
+++ b/static/js/typing.js
@@ -43,7 +43,7 @@ function is_valid_conversation() {
 }
 
 function get_current_time() {
-    return new Date().getTime();
+    return Date.now();
 }
 
 function notify_server_start(user_ids_array) {