diff --git a/Libraries/Core/InitializeCore.js b/Libraries/Core/InitializeCore.js
index 8f12f11b86..e00120aa4b 100644
--- a/Libraries/Core/InitializeCore.js
+++ b/Libraries/Core/InitializeCore.js
@@ -29,6 +29,7 @@
 const start = Date.now();
 
 require('./setUpGlobals');
+require('./setUpPerformance');
 require('./setUpSystrace');
 require('./setUpErrorHandling');
 require('./polyfillPromise');
diff --git a/Libraries/Core/setUpPerformance.js b/Libraries/Core/setUpPerformance.js
new file mode 100644
index 0000000000..6fd0a1e42b
--- /dev/null
+++ b/Libraries/Core/setUpPerformance.js
@@ -0,0 +1,26 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ * @format
+ */
+
+'use strict';
+
+if (!global.performance) {
+  global.performance = {};
+}
+
+/**
+ * Returns a double, measured in milliseconds.
+ * https://developer.mozilla.org/en-US/docs/Web/API/Performance/now
+ */
+if (typeof global.performance.now !== 'function') {
+  global.performance.now = function() {
+    const performanceNow = global.nativePerformanceNow || Date.now;
+    return performanceNow();
+  };
+}
diff --git a/Libraries/Performance/Systrace.js b/Libraries/Performance/Systrace.js
index dcc8555c9a..e1db39bbfc 100644
--- a/Libraries/Performance/Systrace.js
+++ b/Libraries/Performance/Systrace.js
@@ -87,11 +87,25 @@ const userTimingPolyfill = __DEV__
     }
   : null;
 
+function installPerformanceHooks(polyfill) {
+  if (polyfill) {
+    if (global.performance === undefined) {
+      global.performance = {};
+    }
+
+    Object.keys(polyfill).forEach(methodName => {
+      if (typeof global.performance[methodName] !== 'function') {
+        global.performance[methodName] = polyfill[methodName];
+      }
+    });
+  }
+}
+
 const Systrace = {
   installReactHook() {
     if (_enabled) {
       if (__DEV__) {
-        global.performance = userTimingPolyfill;
+        installPerformanceHooks(userTimingPolyfill);
       }
     }
     _canInstallReactHook = true;
@@ -108,8 +122,8 @@ const Systrace = {
             global.nativeTraceEndLegacy(TRACE_TAG_JS_VM_CALLS);
         }
         if (_canInstallReactHook) {
-          if (enabled && global.performance === undefined) {
-            global.performance = userTimingPolyfill;
+          if (enabled) {
+            installPerformanceHooks(userTimingPolyfill);
           }
         }
       }
diff --git a/React/CxxBridge/JSCExecutorFactory.mm b/React/CxxBridge/JSCExecutorFactory.mm
index 411a083dc3..d93a28077b 100644
--- a/React/CxxBridge/JSCExecutorFactory.mm
+++ b/React/CxxBridge/JSCExecutorFactory.mm
@@ -24,6 +24,13 @@ std::unique_ptr<JSExecutor> JSCExecutorFactory::createJSExecutor(
       _RCTLogJavaScriptInternal(static_cast<RCTLogLevel>(logLevel), [NSString stringWithUTF8String:message.c_str()]);
     };
     react::bindNativeLogger(runtime, iosLoggingBinder);
+
+    react::PerformanceNow iosPerformanceNowBinder = []() {
+      // CACurrentMediaTime() returns the current absolute time, in seconds
+      return CACurrentMediaTime() * 1000;
+    };
+    react::bindNativePerformanceNow(runtime, iosPerformanceNowBinder);
+
     // Wrap over the original runtimeInstaller
     if (runtimeInstaller) {
       runtimeInstaller(runtime);
diff --git a/ReactAndroid/src/main/java/com/facebook/hermes/reactexecutor/OnLoad.cpp b/ReactAndroid/src/main/java/com/facebook/hermes/reactexecutor/OnLoad.cpp
index 8b4dabd0f6..d6cbef092d 100644
--- a/ReactAndroid/src/main/java/com/facebook/hermes/reactexecutor/OnLoad.cpp
+++ b/ReactAndroid/src/main/java/com/facebook/hermes/reactexecutor/OnLoad.cpp
@@ -14,6 +14,7 @@
 #include <react/jni/JReactMarker.h>
 #include <react/jni/JSLogging.h>
 #include <react/jni/JavaScriptExecutorHolder.h>
+#include <react/jni/NativeTime.h>
 
 #include <memory>
 
@@ -48,6 +49,10 @@ static void installBindings(jsi::Runtime &runtime) {
       static_cast<void (*)(const std::string &, unsigned int)>(
           &reactAndroidLoggingHook);
   react::bindNativeLogger(runtime, androidLogger);
+
+  react::PerformanceNow androidNativePerformanceNow =
+      static_cast<double (*)()>(&reactAndroidNativePerformanceNowHook);
+  react::bindNativePerformanceNow(runtime, androidNativePerformanceNow);
 }
 
 class HermesExecutorHolder
diff --git a/ReactAndroid/src/main/java/com/facebook/react/jscexecutor/OnLoad.cpp b/ReactAndroid/src/main/java/com/facebook/react/jscexecutor/OnLoad.cpp
index f4e1783fee..e05dfec2ef 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/jscexecutor/OnLoad.cpp
+++ b/ReactAndroid/src/main/java/com/facebook/react/jscexecutor/OnLoad.cpp
@@ -11,6 +11,7 @@
 #include <react/jni/JReactMarker.h>
 #include <react/jni/JSLogging.h>
 #include <react/jni/JavaScriptExecutorHolder.h>
+#include <react/jni/NativeTime.h>
 #include <react/jni/ReadableNativeMap.h>
 
 #include <memory>
@@ -30,6 +31,10 @@ class JSCExecutorFactory : public JSExecutorFactory {
           static_cast<void (*)(const std::string &, unsigned int)>(
               &reactAndroidLoggingHook);
       react::bindNativeLogger(runtime, androidLogger);
+
+      react::PerformanceNow androidNativePerformanceNow =
+          static_cast<double (*)()>(&reactAndroidNativePerformanceNowHook);
+      react::bindNativePerformanceNow(runtime, androidNativePerformanceNow);
     };
     return std::make_unique<JSIExecutor>(
         jsc::makeJSCRuntime(),
diff --git a/ReactAndroid/src/main/jni/react/jni/NativeTime.cpp b/ReactAndroid/src/main/jni/react/jni/NativeTime.cpp
new file mode 100644
index 0000000000..05eb72b49b
--- /dev/null
+++ b/ReactAndroid/src/main/jni/react/jni/NativeTime.cpp
@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include "NativeTime.h"
+#include <chrono>
+
+namespace facebook {
+namespace react {
+
+double reactAndroidNativePerformanceNowHook() {
+  auto time = std::chrono::steady_clock::now();
+  auto duration = std::chrono::duration_cast<std::chrono::nanoseconds>(
+                      time.time_since_epoch())
+                      .count();
+
+  constexpr double NANOSECONDS_IN_MILLISECOND = 1000000.0;
+
+  return duration / NANOSECONDS_IN_MILLISECOND;
+}
+
+} // namespace react
+} // namespace facebook
diff --git a/ReactAndroid/src/main/jni/react/jni/NativeTime.h b/ReactAndroid/src/main/jni/react/jni/NativeTime.h
new file mode 100644
index 0000000000..b4d028dd88
--- /dev/null
+++ b/ReactAndroid/src/main/jni/react/jni/NativeTime.h
@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+namespace facebook {
+namespace react {
+
+double reactAndroidNativePerformanceNowHook();
+
+} // namespace react
+} // namespace facebook
diff --git a/ReactCommon/jsiexecutor/jsireact/JSIExecutor.cpp b/ReactCommon/jsiexecutor/jsireact/JSIExecutor.cpp
index 0cf45f52df..3fb689543d 100644
--- a/ReactCommon/jsiexecutor/jsireact/JSIExecutor.cpp
+++ b/ReactCommon/jsiexecutor/jsireact/JSIExecutor.cpp
@@ -483,5 +483,20 @@ void bindNativeLogger(Runtime &runtime, Logger logger) {
           }));
 }
 
+void bindNativePerformanceNow(Runtime &runtime, PerformanceNow performanceNow) {
+  runtime.global().setProperty(
+      runtime,
+      "nativePerformanceNow",
+      Function::createFromHostFunction(
+          runtime,
+          PropNameID::forAscii(runtime, "nativePerformanceNow"),
+          0,
+          [performanceNow = std::move(performanceNow)](
+              jsi::Runtime &runtime,
+              const jsi::Value &,
+              const jsi::Value *args,
+              size_t count) { return Value(performanceNow()); }));
+}
+
 } // namespace react
 } // namespace facebook
diff --git a/ReactCommon/jsiexecutor/jsireact/JSIExecutor.h b/ReactCommon/jsiexecutor/jsireact/JSIExecutor.h
index 48333c45c1..8245e3fd3f 100644
--- a/ReactCommon/jsiexecutor/jsireact/JSIExecutor.h
+++ b/ReactCommon/jsiexecutor/jsireact/JSIExecutor.h
@@ -135,5 +135,10 @@ class JSIExecutor : public JSExecutor {
 using Logger =
     std::function<void(const std::string &message, unsigned int logLevel)>;
 void bindNativeLogger(jsi::Runtime &runtime, Logger logger);
+
+using PerformanceNow = std::function<double()>;
+void bindNativePerformanceNow(
+    jsi::Runtime &runtime,
+    PerformanceNow performanceNow);
 } // namespace react
 } // namespace facebook