---
title: OptimizelyConfig for the JavaScript SDK v6+
slug: feature-experimentation/docs/optimizelyconfig-for-the-javascript-sdk
docTags: 
createdAt: 2026-08-05T20:40:01.000Z
---

Optimizely Feature Experimentation SDKs open a well-defined set of public APIs, hiding implementation details. However, you may need access to project configuration data within the [datafile](docId:3LmHm4b3kTxKBuoR93KN8). The following section extends the public APIs to define data models and access methods, which you can use to access project configuration data.

## Minimum SDK version

v6.0.0+

For versions 5.3.5 and below, see [JavaScript (Browser) SDK](docId\:peAwVyvLK6ZSxsbszaiO6) or [JavaScript (Node) SDK](docId\:hKhtxowJe_Iz6e6f2QOZ-). See the [SDK compatibility matrix](docId:2shbZfPCkPAZ0mlZpL1TU) documentation for a list of current SDK releases and the features they support.

A public configuration data model (OptimizelyConfig) is defined as a structured format of static Optimizely Project data.

### Get `OptimizelyConfig`

You can access `OptimizelyConfig` through the `OptimizelyClient` (top-level) using this public API call.

```javascript
const config = optimizely.getOptimizelyConfig();
```

`getOptimizelyConfig` returns an `OptimizelyConfig` instance, which includes the following:

- Environment key
- SDK key
- Datafile revision number
- Experiments mapped by key values
- All attributes
- All audiences
- All events
- Feature flags mapped by their key values

:::hint{type="info"}
When the system updates the datafile, you can add a [OptimizelyConfigUpdate notification listener](#)  to get notified. After receiving the notification, call the method to get the updated `OptimizelyConfig` data.
:::

### Get datafile

To share the same datafile between multiple SDK instances (for example, in a client and server scenario), you can pass a JSON string representation of the config (the datafile) between the instances. To get the datafile, use the `OptimizelyConfig` object's `getDatafile` method. For information, see [Sharing the datafile with multiple SDK implementations](docId\:eH-UMm_rOn_GdGDGLV6__).

### Object model

The following sample shows the object model for `OptimizelyConfig`:

```typescript
export interface OptimizelyConfig {
  environmentKey: string;
  sdkKey: string;
  revision: string;

  /**
   * This experimentsMap is for experiments of legacy projects only.
   * For flag projects, experiment keys are not guaranteed to be unique
   * across multiple flags, so this map may not include all experiments
   * when keys conflict.
   */
  experimentsMap: OptimizelyExperimentsMap;

  featuresMap: OptimizelyFeaturesMap;
  attributes: OptimizelyAttribute[];
  audiences: OptimizelyAudience[];
  events: OptimizelyEvent[];
  getDatafile(): string;
}

export type OptimizelyExperimentsMap = {
  [experimentKey: string]: OptimizelyExperiment;
}

export interface OptimizelyExperiment {
  id: string;
  key: string;
  audiences: string;
  variationsMap: {
    [variationKey: string]: OptimizelyVariation;
  };
}

export interface OptimizelyVariation {
  id: string;
  key: string;
  featureEnabled?: boolean;
  variablesMap: OptimizelyVariablesMap;
}

export type OptimizelyVariablesMap = {
  [variableKey: string]: OptimizelyVariable;
}

export interface OptimizelyVariable {
  id: string;
  key: string;
  type: string;
  value: string;
}

export type OptimizelyFeaturesMap = {
  [featureKey: string]: OptimizelyFeature;
}

export interface OptimizelyFeature {
  id: string;
  key: string;
  experimentRules: OptimizelyExperiment[];
  deliveryRules: OptimizelyExperiment[];
  variablesMap: OptimizelyVariablesMap;

  /**
   * @deprecated Use experimentRules and deliveryRules
   */
  experimentsMap: OptimizelyExperimentsMap;
}

export type OptimizelyAttribute = {
  id: string;
  key: string;
};

export type OptimizelyAudience = {
  id: string;
  name: string;
  conditions: string;
};

export type OptimizelyEvent = {
  id: string;
  key: string;
  experimentIds: string[];
};
```

## Examples

You can access `OptimizelyConfig` from the `OptimizelyClient` (top-level) using the following code example:

```javascript
import { NOTIFICATION_TYPES } from '@optimizely/optimizely-sdk';

const config = optimizely.getOptimizelyConfig();

console.log(`[OptimizelyConfig] revision = ${config.revision}`);
console.log(`[OptimizelyConfig] sdkKey = ${config.sdkKey}`);
console.log(`[OptimizelyConfig] environmentKey = ${config.environmentKey}`);

console.log(`[OptimizelyConfig] attributes:`);
config.attributes.forEach((attribute) => {
  console.log(`[OptimizelyAttribute]   -- (id, key) = (${attribute.id}, ${attribute.key})`);
});

console.log(`[OptimizelyConfig] audiences:`);
config.audiences.forEach((audience) => {
  console.log(
    `[OptimizelyAudience]   -- (id, name, conditions) = (${audience.id}, ${audience.name}, ${audience.conditions})`
  );
});

console.log(`[OptimizelyConfig] events:`);
config.events.forEach((event) => {
  console.log(
    `[OptimizelyEvent]   -- (id, key, experimentIds) = (${event.id}, ${event.key}, ${event.experimentIds})`
  );
});

// all flags
const flags = [];
const flagKeys = [];
for (let key in config.featuresMap) {
  flags.push(config.featuresMap[key]);
  flagKeys.push(key);
}

flagKeys.forEach((flagKey) => {
  const flag = config.featuresMap[flagKey];

  const experimentRules = flag.experimentRules;
  const deliveryRules = flag.deliveryRules;

  // use experiment rules and delivery rules and other flag data here...

  experimentRules.forEach((experiment) => {
    console.log(`[OptimizelyExperiment]   - experiment rule-key = ${experiment.key}`);
    console.log(`[OptimizelyExperiment]   - experiment audiences = ${experiment.audiences}`);

    const variationsMap = experiment.variationsMap;
    const variationKeys = [];

    for (let key in variationsMap) {
      variationKeys.push(key);
    }

    variationKeys.forEach((varKey) => {
      const variation = variationsMap[varKey];
      console.log(
        `[OptimizelyVariation]       -- variation = { key: ${varKey}, id: ${variation.id}, featureEnabled: ${variation.featureEnabled} })`
      );

      const variablesMap = variationsMap[varKey].variablesMap;
      const variableKeys = [];

      for (let key in variablesMap) {
        variableKeys.push(key);
      }

      variableKeys.forEach((variableKey) => {
        const variable = variablesMap[variableKey];
        console.log(`[OptimizelyVariable]           --- variable: ${variableKey}, ${variable}`);
      });
    });
  });

  deliveryRules.forEach((delivery) => {
    console.log(`[OptimizelyExperiment]   - delivery rule-key = ${delivery.key}`);
    console.log(`[OptimizelyExperiment]   - delivery audiences = ${delivery.audiences}`);

    // use delivery rule data here...
  });
});

// listen to OPTIMIZELY_CONFIG_UPDATE to get updated data
optimizely.notificationCenter.addNotificationListener(
  NOTIFICATION_TYPES.OPTIMIZELY_CONFIG_UPDATE,
  () => {
    const newConfig = optimizely.getOptimizelyConfig();
    console.log(`[OptimizelyConfig] revision = ${newConfig.revision}`);
  }
);
```