Measure Tree, Building & Object Height With Your Phone
Use your smartphone camera, measurement geometry and supported AR technology to measure the height of trees, buildings, poles and other vertical objects.
Accuracy depends on device capabilities, camera positioning, distance and user technique.
Try It Now — Height Calculator
Enter your distance and angles to calculate height instantly. Imperial and metric supported. For camera + phone sensor measurement, use the camera flow.
How Does Phone Height Measurement Work?
Phone height measurement combines a few simple ideas: camera aiming, phone orientation sensors, the angle of elevation to the top of an object, the horizontal distance to that object, and trigonometry. When the phone knows how far you are from an object and the angle up to its top, trigonometry can recover the object's height.
Your phone reports its tilt using a gyroscope and accelerometer. When you aim the camera at the base of an object and then at its top, Measure reads those inclination angles. Combined with the horizontal distance — which you can enter manually, approximate with GPS, or (on supported devices) measure with AR — the app converts the angles into a real-world height using the tangent function.
The two-angle method is especially useful because it does not assume the ground is level. By measuring both the angle to the top and the angle to the base, the calculation automatically handles an object base that sits above or below you. On devices with AR or depth support, distance can be measured more directly; on standard devices, you provide the distance and the app focuses on the angles.
Because small angle errors become large height errors at steep angles, Measure also reports a confidence score and an estimated uncertainty range, so you can judge how much to trust the result rather than receiving a single bare number.
How to Measure a Tree Height With Your Phone
- Stand where the entire tree is visible, from the base of the trunk to the highest point.
- Determine your horizontal distance from the trunk.
- Aim at the tree base and mark the base angle.
- Aim at the highest visible point of the tree and mark the top angle.
- Let Measure calculate the height.
- Leaning trees — aim at the true base and the highest foliage point, not the lean direction.
- Sloped ground — use the two-angle method so the base angle is accounted for.
- Hidden tree base — move until the base is visible or estimate carefully.
- Unclear treetop — pick the highest visible foliage or branch tip.
- Standing too close — steep angles amplify error; step back.
How to Measure a Building Height With Your Phone
- Identify the building base at ground level where the wall meets the ground.
- Determine your horizontal distance to the wall.
- Aim at the base, then aim at the roofline.
- Avoid measuring antennae or rooftop equipment unless you intend to include them.
- On sloped terrain, use the two-angle method.
Works for houses, office buildings, barns, warehouses and towers. For very tall structures, move farther back to keep the top angle reasonable.
The Math Behind the Measurement
Trigonometry relates the angle of a right triangle to the ratio of its sides: tan(angle) = opposite / adjacent. In a height measurement, the "opposite" side is the height difference between the phone and the point you are aiming at, and the "adjacent" side is the horizontal distance to the object.
So the height difference equals distance multiplied by tan(angle). When you measure both a top angle and a base angle, the full object height is:
Object Height = Distance × [tan(Top Angle) − tan(Base Angle)]
If Distance = 60 ft, Top Angle = 45°, and Base Angle = 0°:
Height = 60 × tan(45°) = 60 × 1 ≈ 60 ft
With a non-zero base angle, the subtraction term keeps the result correct even when the object base is below you.
What Can You Measure?
How Accurate Is Phone Height Measurement?
Measure does not publish a single accuracy percentage. Results depend on distance accuracy, phone sensor calibration, camera angle, your ability to identify the true base and top, terrain slope, device sensor quality, hand movement and any AR or depth support.
This tool is appropriate for estimates and general measurement. It should not replace professional surveying equipment where certified or engineering-grade measurements are required.
How to Get a More Accurate Measurement
- Stand farther back from very tall objects to avoid extreme upward angles.
- Keep the phone steady while capturing each angle.
- Accurately measure the horizontal distance — this is the biggest source of error.
- Identify the true base of the object at ground level.
- Use the highest structural point you actually intend to measure.
- Avoid extreme upward viewing angles.
- Repeat the measurement several times and compare.
- Use AR or depth distance measurement when available.
- Calibrate device sensors if prompted or if readings seem off.
How Your Phone Measures Height
Measure uses your phone's camera, gyroscope and accelerometer to read angles, and AR or depth sensing where available to measure distance. Not all phones have LiDAR; Measure is designed to work across a range of devices.
Phones with LiDAR or dedicated depth sensors. Richest distance and depth data, highest confidence.
Phones supporting ARKit/ARCore. Good geometry-based distance, moderate-to-high confidence.
Camera + gyroscope/accelerometer only. Works with manual or GPS distance and wider uncertainty.
Measured vs. Estimated Results
Results from Measure should be considered estimates unless independently verified:
- Manually entered distance can introduce error.
- Phone angle sensors have tolerances.
- AR-derived distances may differ by device.
- Results are estimates, not survey-grade measurements.
What Can a Phone Height Measurement Tool Be Used For?
Not intended for licensed engineering or surveying work.
Related Calculators
Measure App Frequently Asked Questions
Can I measure the height of a tree with my phone?
Yes. Measure uses your phone camera, device inclination sensors and the horizontal distance from the trunk to estimate tree height with trigonometry. Stand back far enough to see the whole tree, aim at the base, aim at the highest visible point, and let Measure calculate the height. The result is an estimate, not a certified measurement.
Can my phone measure building height?
Yes, for most ordinary buildings. Aim at the base of the wall and the roofline, enter or measure your horizontal distance, and Measure computes the height. Tall structures may require standing farther back. Avoid aiming at antennae or rooftop equipment unless you intend to include them.
How does the app calculate height?
Measure uses the tangent relationship from trigonometry. With the horizontal distance D and the angles to the top and base of the object, it calculates height as D multiplied by (tan(top angle) minus tan(base angle)). In single-angle mode it adds your camera or eye height to D times tan(top angle). Angles are converted from degrees to radians internally.
Do I need LiDAR?
No. LiDAR and dedicated depth sensors can improve distance and accuracy on supported devices, but Measure works with a standard camera and phone orientation sensors using trigonometry. Depth-enhanced devices simply produce more confident results; a standard camera device still runs a measurement with a wider uncertainty range.
Does Measure work on Android?
Yes. Measure runs in the browser on Android, and the native Measure app can use Android camera APIs and ARCore where available for AR distance. The manual calculator works on any device with a browser.
Does Measure work on iPhone?
Yes. Measure runs in the browser on iPhone, and the native Measure app can use iPhone cameras and, on supported models, LiDAR for more accurate depth. The manual calculator works in the browser on any iPhone.
How far should I stand from a tree?
Far enough that the whole tree fits comfortably in the camera view and the angle to the top is not extreme. A rough guide is to stand roughly as far from the tree as it is tall. Standing too close creates very steep angles that amplify small errors; standing too far makes the angle small and harder to read precisely.
How accurate is camera-based height measurement?
Accuracy depends on distance accuracy, phone sensor calibration, camera angle, your ability to identify the true base and top, terrain slope, device sensor quality, hand movement and any AR or depth support. Measure shows a confidence score and an estimated uncertainty range. It is appropriate for estimates and general measurement, not for certified or engineering-grade work.
Can I measure a building from the ground?
Yes. Stand on level ground where you can see the base and roofline, determine your horizontal distance to the wall, aim at the base, then the roofline, and calculate. For very tall buildings, move farther back or use a vantage point that keeps the top angle reasonable.
What if the ground slopes?
Use the two-angle method. Aiming at both the base and the top accounts for the object base being above or below you, because the base angle is subtracted from the top angle in the formula. This is more reliable than assuming the ground is level.
Can I measure telephone poles?
Yes. Treat a pole like any vertical object: stand back, aim at the base and the top, and enter your horizontal distance. Make sure you have a clear line of sight and stay a safe distance from any electrical equipment.
Can I measure a tower?
Yes, within limits. Tall towers may require a long distance to keep the top angle reasonable and a clear line of sight. Aim at the highest structural point you intend to measure, not attached antennae unless you want to include them.
How do I measure distance to the object?
You can enter a distance manually (for example from a tape measure, map, or known pace length), use GPS walk-to-measure for an approximate distance, or use AR distance on supported devices. Manual distance is usually the most precise; GPS distance is approximate and should be treated as lower precision.
What happens if I cannot see the object's base?
If the base is hidden, estimate the base position as best you can or move until it is visible. A hidden or guessed base introduces error, so the confidence score will be lower. Where possible, move to a spot with a clear view of both the base and the top.
Can this replace professional surveying equipment?
No. Measure is an estimating tool. It should not replace professional surveying equipment where certified, legal or engineering-grade measurements are required. For those needs, use qualified professionals and appropriate instruments.
Ready to Measure Something?
Point your phone at a tree, building or other vertical object and use Measure to calculate its height.
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