Camera measurement
Sight an angle through your camera
Aim your camera at a roofline, a tree or a slope, and read the angle of elevation off the tilt sensor.
Height from the angle
Aim the crosshair at the top of what you are measuring, then enter how far away you are standing.
Estimated height
1.60 m
The crosshair is fixed to the centre of the frame on purpose. A browser cannot read your camera's field of view, so an angle to any other point on screen would be guesswork. Aim the centre at your target.
About this tool
Aim your camera at a roofline, a tree or a slope and read the angle of elevation. Add the distance to work out the height, and hold the reading to note it down.
How camera measurement works
The camera is only there to aim with. The angle itself comes from your phone’s tilt sensor: when the crosshair in the middle of the frame points at something, the phone is tilted up or down by exactly the angle of elevation to it. That is why the crosshair is fixed in the centre. A browser cannot read your camera’s field of view, so an angle to any other point on the screen would be a guess.
Finding a height
- Stand on level ground, a measured distance from the base of what you are measuring.
- Aim the crosshair at the top and hold the reading.
- Enter the distance and your eye height. The page multiplies the distance by the tangent of the angle and adds your eye height.
How far to trust the answer
The height can only be as good as the distance you enter: a distance 10% too long gives a height 10% too tall. Aiming matters too. At 15 m and 50°, an aim that is 1° high adds about 0.6 m to the height, and the error grows quickly as the angle steepens. Stand back about as far as the object is tall, steady the phone against something, and take the reading two or three times.
For a picture you have already taken, or an angle on a surface rather than an elevation, use photo measurement instead.
Frequently asked questions
How do you take measurements with your phone camera?
It depends on what you want to measure. For lengths, such as the width of a table, use an augmented-reality measuring app like Apple’s Measure app on iPhone, which estimates distances from the camera image and the phone’s motion sensors.
For angles and heights, use this page: aim the crosshair at the top of a roofline, a tree or a slope and read the angle of elevation from the phone’s tilt sensor, then enter how far away you are standing to get the height. To measure an angle in a picture you have already taken, use photo measurement.
How do you measure the height of a tree or building with your phone?
Stand a known distance from the base, sight the top through the camera and read the angle of elevation. The height above your eyes is the distance multiplied by the tangent of that angle; add your eye height to get the total.
Example: standing 15 m from a building, you sight the top of the wall at 50°. 15 × tan 50° ≈ 17.9 m, and adding an eye height of about 1.6 m makes the building about 19.5 m tall. This page does the sum for you. It works best on level ground, standing back about as far as the object is tall, where a small aiming error matters least. See angles of elevation for why it works.
Guides
About these measurements
Readings are estimates taken from rendered pixels and consumer device sensors. Do not rely on them for structural engineering, surveying, manufacturing inspection, navigation, or medical decisions. Check anything safety-critical with a calibrated instrument.
All processing happens in your browser. No image, camera frame or sensor reading is ever uploaded.
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