How to measure a room with your phone
You can measure a room and get accurate interior dimensions with an iPhone or iPad Pro using its LiDAR sensor and a scanning app. Walk the room and the app builds a measured floor plan with square footage and wall lengths, usually within an inch or two. A regular iPhone can measure a single wall with Apple's Measure app; for a full floor plan you need a LiDAR device and a scanning app like Chalk.
Measure a room in about three minutes.
1. Check your phone has a LiDAR sensor
For a full measured floor plan you need LiDAR, which is on iPhone Pro and Pro Max models (iPhone 12 Pro and later) and iPad Pro (2020 and later). Any recent iPhone can measure a single wall length with Apple's Measure app, but LiDAR is what builds room dimensions and a plan.
2. Open a scanning app
Open a LiDAR room-scanning app such as Chalk. For a quick single distance you can use Apple's built-in Measure app instead, but it will not produce a full floor plan.
3. Stand in a corner and start the scan
Begin in a corner of the room so the app has a clear reference. Hold the phone up at chest height with the camera facing the walls.
4. Walk the perimeter slowly
Move slowly around the room, keeping the walls, floor, and ceiling line in frame. Pan across doors, windows, and openings so they are captured in the plan.
5. Review the measured plan
The app produces a floor plan with wall lengths, room dimensions, and total square footage, usually within an inch or two at room scale. Check the corners and openings look right.
6. Save, export, or attach it
Export the floor plan as a PDF or image, or, in a tool like Chalk, save it straight onto the job record with your photos so the measurement lives with the evidence.
You need LiDAR for a floor plan.
Full measured floor plan
iPhone Pro and Pro Max (iPhone 12 Pro and later) and iPad Pro (2020 and later). These have the LiDAR sensor that builds room dimensions and a plan.
Single wall or distance only
Most recent iPhones can measure one straight length with Apple's Measure app, but cannot produce a floor plan without LiDAR.
The number has to hold up.
A guessed square footage is a number someone gets to argue with, an adjuster, a client, a subcontractor. A measured floor plan captured on your phone turns the argument into a lookup. In Chalk, that plan lands on the job record next to your photos, so the measurement and the evidence live together, ready for the carrier or the client.
Measuring a room with your phone, answered.
Can I measure a room with a regular (non-Pro) iPhone?
You can measure a single straight distance with Apple's Measure app on most recent iPhones, but you cannot build a full measured floor plan without a LiDAR sensor. LiDAR is only on iPhone Pro and Pro Max models (iPhone 12 Pro and later) and iPad Pro (2020 and later).
How accurate is measuring a room with your phone?
With a LiDAR sensor and a good scanning pass, room-scale measurements are usually accurate within an inch or two. Accuracy is best in normal lighting, with the phone held steady and the walls kept in frame.
What app measures interior dimensions and floor plans?
LiDAR scanning apps that use Apple's RoomPlan technology can produce a measured floor plan. Chalk captures interior dimensions, a floor plan, and a 3D dollhouse view, and saves them onto the job record alongside your photos and documents.
Do I need an internet connection to scan a room?
You capture the scan on the property whether or not you have signal. In Chalk, the scan processes into a finished floor plan once you are back in range, so a dead zone does not stop you from measuring.
What is the difference between measured and estimated square footage?
Estimated square footage is a guess from a tape here and there or from memory. A measured floor plan captures the actual dimensions of every wall and room, so the number holds up when a carrier, client, or subcontractor questions it.
