Overview

This page describes how to instrument your React application with the Datadog Feature Flags SDK. Datadog feature flags provide a unified way to remotely control feature availability in your app, experiment safely, and deliver new experiences with confidence.

The Datadog Feature Flags SDK for React is built on OpenFeature, an open standard for feature flag management. This guide explains how to install the SDK, configure the Datadog provider, and evaluate flags in your React components.

Installation

Install the Datadog OpenFeature provider and the OpenFeature React SDK using your preferred package manager:

npm install @datadog/openfeature-browser @openfeature/react-sdk @openfeature/core

yarn add @datadog/openfeature-browser @openfeature/react-sdk @openfeature/core

pnpm add @datadog/openfeature-browser @openfeature/react-sdk @openfeature/core

Initialize the provider

Create a DatadogProvider instance and register it with OpenFeature. Do this as early as possible in your application, before rendering your React components. To create a client token, see Client tokens.

import { DatadogProvider } from '@datadog/openfeature-browser';

const provider = new DatadogProvider({
  applicationId: '<APPLICATION_ID>',
  clientToken: '<CLIENT_TOKEN>',
  site: '',
  env: '<ENV_NAME>',
});

Set the evaluation context

Define who or what the flag evaluation applies to using an evaluation context. The evaluation context includes user or session information used to determine which flag variations should be returned. Reference these attributes in your targeting rules to control who sees each variant.

Set the provider along with the evaluation context:

import { OpenFeature } from '@openfeature/react-sdk';

const evaluationContext = {
  targetingKey: 'user-123',
  user_id: '123',
  email: 'user@example.com',
  tier: 'premium',
};

OpenFeature.setProvider(provider, evaluationContext);

Wrap your application

Wrap your application with the OpenFeatureProvider component. This makes feature flags available to all child components through React context.

import { OpenFeatureProvider } from '@openfeature/react-sdk';

function App() {
  return (
    <OpenFeatureProvider>
      <YourApp />
    </OpenFeatureProvider>
  );
}

Evaluate flags

The OpenFeature React SDK provides hooks for evaluating flags within your components. Each hook returns the flag value based on the evaluation context you configured.

Boolean flags

Use useBooleanFlagValue(key, defaultValue) for flags that represent on/off or true/false conditions:

import { useBooleanFlagValue } from '@openfeature/react-sdk';

function CheckoutButton() {
  const isNewCheckoutEnabled = useBooleanFlagValue('new_checkout_button', false);

  if (isNewCheckoutEnabled) {
    return <NewCheckoutButton />;
  }

  return <LegacyCheckoutButton />;
}

String flags

Use useStringFlagValue(key, defaultValue) for flags that select between multiple variants or configuration strings:

import { useStringFlagValue } from '@openfeature/react-sdk';

function ThemedComponent() {
  const theme = useStringFlagValue('ui_theme', 'light');

  switch (theme) {
    case 'dark':
      return <DarkTheme />;
    case 'light':
    default:
      return <LightTheme />;
  }
}

Number flags

Use useNumberFlagValue(key, defaultValue) for numeric flags such as limits, percentages, or multipliers:

import { useNumberFlagValue } from '@openfeature/react-sdk';

function CartDisplay() {
  const maxItems = useNumberFlagValue('max_cart_items', 20);

  return <Cart maxItems={maxItems} />;
}

Object flags

Use useObjectFlagValue(key, defaultValue) for structured configuration data:

import { useObjectFlagValue } from '@openfeature/react-sdk';

function Banner() {
  const config = useObjectFlagValue('promo_banner', {
    color: '#00A3FF',
    message: 'Welcome!',
  });

  return <PromoBanner color={config.color} message={config.message} />;
}

Suspense support

Built-in suspense support allows you to avoid displaying components with feature flags until provider initialization is complete, or when the context changes. Pass { suspend: true } in the hook options to use this functionality.

For example:

import { useBooleanFlag } from '@openfeature/react-sdk';
import { Suspense } from 'react';

import
function Content() {
  // Display a loading message if the component uses feature flags and the provider is not ready
  return (
    <Suspense fallback={"Loading..."}>
      <WelcomeMessage />
    </Suspense>
  );
}

function WelcomeMessage() {
  const { value: showNewMessage } = useBooleanFlag('show-new-welcome-message', false, { suspend: true });

  return (
    <>
      {showNewMessage ? (
        <p>Welcome! You're seeing the new experience.</p>
      ) : (
        <p>Welcome back!</p>
      )}
    </>
  );
}

Flag evaluation details

When you need more than just the flag value, use the detail hooks. These return both the evaluated value and metadata explaining the evaluation:

• useBooleanFlagDetails(key, defaultValue)
• useStringFlagDetails(key, defaultValue)
• useNumberFlagDetails(key, defaultValue)
• useObjectFlagDetails(key, defaultValue)

For example:

import { useStringFlagDetails } from '@openfeature/react-sdk';

function PaywallLayout() {
  const details = useStringFlagDetails('paywall_layout', 'control');

  console.log(details.value);   // Evaluated value (for example: "A", "B", or "control")
  console.log(details.variant); // Variant name, if applicable
  console.log(details.reason);  // Description of why this value was chosen

  return <Layout variant={details.value} />;
}

Flag details help you debug evaluation behavior and understand why a user received a given value.

Complete example

Here’s a complete example showing how to set up and use Datadog Feature Flags in a React application:

import { Suspense } from 'react';
import { DatadogProvider } from '@datadog/openfeature-browser';
import { OpenFeatureProvider, OpenFeature, useBooleanFlagValue } from '@openfeature/react-sdk';

// Initialize the Datadog provider
const provider = new DatadogProvider({
  applicationId: '<APPLICATION_ID>',
  clientToken: '<CLIENT_TOKEN>',
  site: '',
  env: '<ENV_NAME>',
});

// Set the evaluation context
const evaluationContext = {
  targetingKey: 'user-123',
  user_id: '123',
  user_role: 'admin',
};

OpenFeature.setProvider(provider, evaluationContext);

// Wrap your app with the OpenFeatureProvider and Suspense for loading state
function App() {
  return (
    <Suspense fallback={<Loading />}>
      <OpenFeatureProvider suspendUntilReady>
        <Page />
      </OpenFeatureProvider>
    </Suspense>
  );
}

// Use feature flags in your components
function Page() {
  const showNewFeature = useBooleanFlagValue('new_feature', false);

  return (
    <div>
      {showNewFeature ? <NewFeature /> : <ExistingFeature />}
    </div>
  );
}

Update the evaluation context

To update the evaluation context after initialization (for example, when a user logs in), use OpenFeature.setContext():

// When a user logs in
await OpenFeature.setContext({
  targetingKey: user.id,
  user_id: user.id,
  email: user.email,
  plan: user.plan,
});

Testing

You can test against a dedicated Datadog test environment with the real DatadogProvider, or swap it for OpenFeature’s TypedInMemoryProvider to control flag values directly in test code. This section shows the in-memory approach, which keeps tests hermetic and offline. TypedInMemoryProvider is exported from @openfeature/web-sdk; install it as a development dependency and register it before rendering components under test:

import { OpenFeature } from '@openfeature/react-sdk';
import { TypedInMemoryProvider } from '@openfeature/web-sdk';

await OpenFeature.setProviderAndWait(new TypedInMemoryProvider({
  new_checkout_button: {
    variants: { on: true, off: false },
    defaultVariant: 'on',
    disabled: false,
  },
}));

The Web SDK flag shape requires variants, defaultVariant, and disabled. Use setProviderAndWait (not setProvider) to avoid suspense races when the test renders flag-gated components immediately. For component tests that mount a React tree, @openfeature/react-sdk also exports an OpenFeatureTestProvider component that wraps children with an in-memory provider — see the OpenFeature React SDK docs for details.

Further reading

Additional helpful documentation, links, and articles:

Client-Side Feature FlagsDOCUMENTATION OpenFeature React SDKOPENFEATURE Browser MonitoringDOCUMENTATION