Sensor Viewer
View live accelerometer, gyroscope, orientation, compass, light, and proximity readings from your device. Everything runs locally in your browser, nothing is uploaded.
- Runs locally
- No uploads
- Requires permission
- Supported browsers only
Live sensor readings
Move your phone to see supported values update in real time. Desktop browsers have no motion sensors, so use the demo to preview.
Accelerometer
Linear acceleration along three axes, including gravity. A flat, still phone reads about 9.8 on Z.
X-axis
Y-axis
Z-axis
Magnitude
Gyroscope
Rotation rate around each axis. Values near zero mean the device is not turning.
Alpha
Beta
Gamma
Orientation & compass
How the device is held relative to the world. Alpha is a compass bearing from magnetic north.
Alpha
Beta
Gamma
Compass heading
Computed tilt
Pitch and roll derived from the accelerometer vector.
Pitch
Roll
Ambient light & proximity
Exposed through the Generic Sensor API, supported on a limited set of browsers and devices.
Ambient light
Proximity
About this tool
Sensor Viewer reads live data from your device's built-in sensors using standard browser APIs. No app install required. Everything runs locally, nothing leaves your device.
Use it to check that a sensor is working, to observe how values change as you move the phone, or to explore what data is available on a given device.
What are these sensors?
- Accelerometer: measures linear acceleration including gravity along three axes (X, Y, Z) in meters per second squared.
- Gyroscope: measures rotational rate in degrees per second around each axis. Values near zero mean the device is not rotating.
- Device orientation: alpha is the compass bearing (0-360), beta is front-back tilt, and gamma is left-right tilt, all in degrees.
- Tilt (pitch/roll): computed from the accelerometer vector. Pitch is forward/backward lean; roll is side-to-side lean.
- Ambient light: illuminance in lux via the Generic Sensor API. Supported on a limited set of browsers and devices.
- Proximity: distance to a nearby object in centimeters. Requires Generic Sensor API support.
Tips
- Open this page on a phone or tablet to see real sensor data. Desktop browsers have no motion sensors.
- On iOS 13 and later, tap "Start sensor check" then allow access in the dialog that appears.
- If ambient light or proximity shows "not supported," your browser or device does not expose the Generic Sensor API for those sensors.
- The compass heading (alpha) is degrees from magnetic north and may need a few seconds to stabilize.
- Use "Load demo values" to preview all readouts on a desktop where no sensors are available.
About the Sensor Viewer
Modern smartphones and tablets pack a surprising number of sensors. This tool surfaces readings from the most common ones directly in your browser, with no app download and no sign-in. Everything processes on-device; sensor data never leaves your browser.
Accelerometer and gravity
The accelerometer reports forces along three perpendicular axes. Because gravity is always pulling down, a stationary phone lying flat shows roughly 9.8 m/s² on the Z axis. The magnitude row shows the Euclidean length of the vector, which equals gravity (about 9.8) when the phone is still and in free fall gives near zero.
Gyroscope
The gyroscope reports how fast the device is rotating around each axis in degrees per second. Values near zero mean the device is not rotating. Rapid flicks across the table produce large spikes. This data feeds motion-based games and VR head-tracking.
Orientation and compass
Device orientation gives three angles that describe how the phone is held relative to the world. The alpha angle is a compass bearing from 0 to 360 degrees. Beta is front-to-back tilt (0 when flat, 90 when upright), and gamma is side-to-side tilt. The compass heading row normalizes alpha into a 0-360 bearing from magnetic north.
Generic Sensor API
Ambient light and proximity sensors use the newer Generic Sensor API, which is currently supported only in Chromium-based browsers with the appropriate hardware. If your device supports them, ambient light reports illuminance in lux and proximity reports the distance to a nearby surface in centimeters.
Frequently asked questions
Why do I see dashes instead of readings?
Dashes mean no sensor data has arrived yet. On desktop computers there are no motion sensors, so values stay at dashes. On a phone, tap "Start sensor check" and grant permission first. Tap "Load demo values" to preview what the tool looks like with data.
What does "not supported" mean for light and proximity?
These sensors use the Generic Sensor API, which is only available in some Chromium-based browsers and only on devices with the matching hardware. Firefox and Safari do not support it as of 2025.
Is my sensor data sent anywhere?
No. All readings stay in your browser tab. There are no analytics, no data collection, and no server calls for the sensor data.
Why does the compass heading drift or jump?
Compass heading from device orientation (alpha) depends on magnetic field calibration. Metal objects, magnets, and electronics nearby can cause interference. Move the phone in a figure-eight pattern to recalibrate the magnetometer, which stabilizes the reading.