react-native-barometer

Provides barometric and altitude information for React Native apps on iOS and Android.

New Architecture only (v2.0.0+)
This library supports only the React Native New Architecture (Turbo Modules). It does not work with the legacy bridge.

Requirements (v2.0.0+)

• React Native >=0.84 with React 19
• New Architecture only — not compatible with the legacy bridge
• iOS 15.1+
• Android API 24+ (minSdk 24)

Legacy bridge / React Native 0.59–0.83 apps should stay on v1.x.

Getting started

yarn add react-native-barometer
# or
npm install react-native-barometer --save

Installation

From React Native 0.60 onward, autolinking handles native setup.

iOS: run pod install in your ios directory after installing the package. The library ships a podspec (react-native-barometer.podspec); you do not need to add a manual pod line when using autolinking.

Add Core Motion usage text to your app’s Info.plist (required for CMAltimeter on iOS):

<key>NSMotionUsageDescription</key>
<string>Your explanation of why the app reads barometric pressure and altitude.</string>

Android: no extra steps beyond a clean rebuild.

Example app

This repository includes an example app under example/ (React Native 0.87, New Architecture):

cd example
npm install
cd ios && bundle exec pod install && cd ..
npx react-native run-ios
# or
npx react-native run-android

The example exercises live useBarometer start/stop, interval presets, resetRelativeAltitude(), getCurrentReading(), authorization status, error banners, QNH calibration, and getAltitude().

Usage

Call isSupported() before watching on devices where a barometer may be absent.

Hook

import {useBarometer} from 'react-native-barometer';

function PressureLabel() {
  const {payload, error, supported, start, stop} = useBarometer({
    autoStart: true,
    interval: 200,
  });

  if (supported === false) {
    return null;
  }
  if (error) {
    return <Text>{error.message}</Text>;
  }
  return <Text>{payload?.pressure.toFixed(2)} hPa</Text>;
}

Imperative API

import Barometer, {STANDARD_PRESSURE_HPA} from 'react-native-barometer';

const supported = await Barometer.isSupported();
if (supported) {
  const watchId = Barometer.watch(
    payload => {
      console.log(payload.pressure, payload.relativeAltitude);
    },
    error => {
      console.warn(error.code, error.message);
    },
  );
}

Payload fields

| Field | Description | | ----- | ----------- | | timestamp | Sample time (ms since Unix epoch) | | pressure | Filtered air pressure in hPa (EMA-smoothed on both platforms) | | altitudeASL | Altitude in metres from the standard atmosphere (1013.25 hPa) | | altitude | Altitude in metres using setLocalPressure() as sea-level reference | | relativeAltitude | Change since observing started, or since the last resetRelativeAltitude() | | verticalSpeed | Rate of change of altitudeASL over the emit interval (m/s), zero on the first sample |

setInterval(ms) is clamped to a minimum of MIN_INTERVAL_MS (50). Default is DEFAULT_INTERVAL_MS (200). setLocalPressure(hPa) ignores non-positive values and falls back to STANDARD_PRESSURE_HPA (1013.25).

TypeScript types ship as lib/index.d.ts. React Native codegen still reads the specs in src/.

Interval is an emit throttle (and Android sampling hint). Changing it does not reset relative altitude. iOS relative altitude still resets if Core Motion is restarted, including when the app returns from background.

Methods

Summary

• isSupported
• getAuthorizationStatus
• setInterval
• setLocalPressure
• resetRelativeAltitude
• getCurrentReading
• watch
• clearWatch
• stopObserving
• useBarometer
• getAltitude

Details

isSupported()

Before using, check to see if barometric updates are supported on the device.

const isSupported = await Barometer.isSupported();

On iOS this is CMAltimeter.isRelativeAltitudeAvailable. Motion permission can still be denied — see getAuthorizationStatus().

getAuthorizationStatus()

const status = await Barometer.getAuthorizationStatus();
// 'notDetermined' | 'denied' | 'restricted' | 'authorized'

On iOS this maps CMAltimeter.authorizationStatus. Android has no barometer permission and always returns 'authorized'.

setInterval()

Optionally request an update interval in ms. The default update rate is (approx) 200ms, i.e. 5Hz.

import {DEFAULT_INTERVAL_MS, MIN_INTERVAL_MS} from 'react-native-barometer';

Barometer.setInterval(1000);

setLocalPressure()

The altitude event contains two altitudes. The first is the standard atmosphere altitude based upon the standard atmospheric pressure of 1013.25hPa. The second is an altitude based upon a pressure that you can configure. You typically use this to calibrate the altitude to a reference altitude, for example the field elevation of an airport.

Barometer.setLocalPressure(985);

resetRelativeAltitude()

Sets the current altitude as the zero point for relativeAltitude without stopping the sensor.

Barometer.resetRelativeAltitude();

getCurrentReading()

Starts observing if needed, resolves with the next payload, then removes that one-shot watch.

const payload = await Barometer.getCurrentReading();

watch()

Barometer.watch(success, error);

Invokes the success callback whenever the pressure or altitude changes. The optional error callback receives { code, message }.

Fatal codes (no_sensor, unauthorized, altimeter_error) stop observing for every watcher. unreliable (Android accuracy) is reported but observing continues.

Returns a watchId (number).

Parameters:

| Name | Type | Required | Description | | ------- | -------- | -------- | ----------- | | success | function | Yes | Invoked at a default interval of 5Hz. Change with setInterval. | | error | function | No | Invoked when the native layer reports an error. |

Example:

const watchId = Barometer.watch(
  payload => {
    console.log(payload.pressure, payload.relativeAltitude);
  },
  error => {
    console.warn(error.code, error.message);
  },
);

clearWatch()

Barometer.clearWatch(watchID);

Parameters:

| Name | Type | Required | Description | | ------- | ------ | -------- | ------------------------------ | | watchID | number | Yes | Id as returned by watch(). |

stopObserving()

Barometer.stopObserving();

Stops observing for all barometric updates and removes every listener.

Updates are paused while the app is in the background and resume on foreground if observing is still requested.

useBarometer()

React hook over the same singleton as watch().

const {
  payload,
  error,
  supported,
  authorizationStatus,
  observing,
  start,
  stop,
} = useBarometer({autoStart: true, interval: 200});

autoStart defaults to true and only starts when isSupported() is true. Unmount calls clearWatch.

getAltitude()

Pure helper for the same barometric formula used natively:

import {getAltitude, STANDARD_PRESSURE_HPA} from 'react-native-barometer';

const metres = getAltitude(STANDARD_PRESSURE_HPA, 1000);