React native biometrics is a simple bridge to native iOS and Android keystore management. It allows you to create public private key pairs that are stored in native keystores and protected by biometric authentication. Those keys can then be retrieved later, after proper authentication, and used to create a cryptographic signature.

using either Yarn:

yarn add react-native-biometrics

or npm:

$ npm install react-native-biometrics --save

$ npx pod-install

On React Native 0.60 the CLI autolink feature links the module while building the app.

This package requires an iOS target SDK version of iOS 10 or higher

Ensure that you have the NSFaceIDUsageDescription entry set in your react native iOS project, or Face ID will not work properly. This description will be presented to the user the first time a biometrics action is taken, and the user will be asked if they want to allow the app to use Face ID. If the user declines the usage of face id for the app, the isSensorAvailable function will indicate biometrics is unavailable until the face id permission is specifically allowed for the app by the user.

This package requires a compiled SDK version of 29 (Android 10.0) or higher

This package is designed to make server authentication using biometrics easier. Here is an image from https://android-developers.googleblog.com/2015/10/new-in-android-samples-authenticating.html illustrating the basic use case:

When a user enrolls in biometrics, a key pair is generated. The private key is stored securely on the device and the public key is sent to a server for registration. When the user wishes to authenticate, the user is prompted for biometrics, which unlocks the securely stored private key. Then a cryptographic signature is generated and sent to the server for verification. The server then verifies the signature. If the verification was successful, the server returns an appropriate response and authorizes the user.

A constant for the touch id sensor type, evaluates to 'TouchID'

Example

import ReactNativeBiometrics, { BiometryTypes } from 'react-native-biometrics'

const rnBiometrics = new ReactNativeBiometrics()

const { biometryType } = await rnBiometrics.isSensorAvailable()

if (biometryType === BiometryTypes.TouchID) {
  //do something fingerprint specific
}

A constant for the face id sensor type, evaluates to 'FaceID'

Example

import ReactNativeBiometrics, { BiometryTypes } from 'react-native-biometrics'

const rnBiometrics = new ReactNativeBiometrics()

const { biometryType } = await rnBiometrics.isSensorAvailable()

if (biometryType === BiometryTypes.FaceID) {
  //do something face id specific
}

A constant for generic Biometrics, evaluates to 'Biometrics'

Example

import ReactNativeBiometrics, { BiometryTypes } from 'react-native-biometrics'

const rnBiometrics = new ReactNativeBiometrics()

const { biometryType } = await rnBiometrics.isSensorAvailable()

if (biometryType === BiometryTypes.Biometrics) {
  //do something face id specific
}

Options Object

Example

import ReactNativeBiometrics from 'react-native-biometrics'

const rnBiometrics = new ReactNativeBiometrics({ allowDeviceCredentials: true })

// Perform operations as normal
// All prompts will allow for fallback to the device's credentials for authentication

Detects what type of biometric sensor is available. Returns a Promise that resolves to an object with details about biometrics availability

Result Object

Example

import ReactNativeBiometrics, { BiometryTypes } from 'react-native-biometrics'

const rnBiometrics = new ReactNativeBiometrics()

rnBiometrics.isSensorAvailable()
  .then((resultObject) => {
    const { available, biometryType } = resultObject

    if (available && biometryType === BiometryTypes.TouchID) {
      console.log('TouchID is supported')
    } else if (available && biometryType === BiometryTypes.FaceID) {
      console.log('FaceID is supported')
    } else if (available && biometryType === BiometryTypes.Biometrics) {
      console.log('Biometrics is supported')
    } else {
      console.log('Biometrics not supported')
    }
  })

Generates a public private RSA 2048 key pair that will be stored in the device keystore. Returns a Promise that resolves to an object providing details about the keys.

Result Object

Example

import ReactNativeBiometrics from 'react-native-biometrics'

const rnBiometrics = new ReactNativeBiometrics()

rnBiometrics.createKeys()
  .then((resultObject) => {
    const { publicKey } = resultObject
    console.log(publicKey)
    sendPublicKeyToServer(publicKey)
  })

Detects if keys have already been generated and exist in the keystore. Returns a Promise that resolves to an object indicating details about the keys.

Result Object

Example

import ReactNativeBiometrics from 'react-native-biometrics'

const rnBiometrics = new ReactNativeBiometrics()
rnBiometrics.biometricKeysExist()
  .then((resultObject) => {
    const { keysExist } = resultObject

    if (keysExist) {
      console.log('Keys exist')
    } else {
      console.log('Keys do not exist or were deleted')
    }
  })

Deletes the generated keys from the device keystore. Returns a Promise that resolves to an object indicating details about the deletion.

Result Object

Example

import ReactNativeBiometrics from 'react-native-biometrics'

const rnBiometrics = new ReactNativeBiometrics()

rnBiometrics.deleteKeys()
  .then((resultObject) => {
    const { keysDeleted } = resultObject

    if (keysDeleted) {
      console.log('Successful deletion')
    } else {
      console.log('Unsuccessful deletion because there were no keys to delete')
    }
  })

Prompts the user for their fingerprint or face id in order to retrieve the private key from the keystore, then uses the private key to generate a RSA PKCS#1v1.5 SHA 256 signature. Returns a Promise that resolves to an object with details about the signature.

**NOTE: No biometric prompt is displayed in iOS simulators when attempting to retrieve keys for signature generation, it only occurs on actual devices.

Options Object

Result Object

Example

import ReactNativeBiometrics from 'react-native-biometrics'

let epochTimeSeconds = Math.round((new Date()).getTime() / 1000).toString()
let payload = epochTimeSeconds   'some message'

const rnBiometrics = new ReactNativeBiometrics()

rnBiometrics.createSignature({
    promptMessage: 'Sign in',
    payload: payload
  })
  .then((resultObject) => {
    const { success, signature } = resultObject

    if (success) {
      console.log(signature)
      verifySignatureWithServer(signature, payload)
    }
  })

Prompts the user for their fingerprint or face id. Returns a Promise that resolves if the user provides a valid biometrics or cancel the prompt, otherwise the promise rejects.

**NOTE: This only validates a user's biometrics. This should not be used to log a user in or authenticate with a server, instead use createSignature. It should only be used to gate certain user actions within an app.

Options Object

Result Object

Example

import ReactNativeBiometrics from 'react-native-biometrics'

const rnBiometrics = new ReactNativeBiometrics()

rnBiometrics.simplePrompt({promptMessage: 'Confirm fingerprint'})
  .then((resultObject) => {
    const { success } = resultObject

    if (success) {
      console.log('successful biometrics provided')
    } else {
      console.log('user cancelled biometric prompt')
    }
  })
  .catch(() => {
    console.log('biometrics failed')
  })

• Because of this library's dependency on androidx.biometric:biometric:1.0.0 it can cause transitive dependency resolution to change on certain version of React Native and androidx.swiperefreshlayout may no longer be able to be resolved. This can be fixed by adding an explicit dependency on the library in your android/app/build.gradle:

  dependencies {
      implementation fileTree(dir: "libs", include: ["*.jar"])
      implementation "com.facebook.react:react-native: "  // From node_modules
      implementation "androidx.swiperefreshlayout:swiperefreshlayout:1.0.0" // temp fix
      ...
  }
  

• There is a known issue on the iOS 13.x simulators where keys generated with access control flags cannot be queried and found properly. This results in key not found errors in biometricKeysExist and createSignature on those simulators. However, it works correctly on actual devices running iOS 13.