How to measure a room with your iPhone

An iPhone can measure a room two ways: one length at a time with Apple's Measure app, or all at once with a LiDAR scan. Which you can use depends on the phone, and which you should use depends on what you are going to do with the numbers. For flooring, here is how to get both right.

Two ways the phone measures

	Measure app	LiDAR room scan
What you get	One length at a time, point to point	The floor outline, the walls, the doors and windows, in one pass
Which iPhones	Any recent iPhone; steadier with LiDAR	Pro and Pro Max models only
You still do	The sketch, and the arithmetic	A check that the scan agrees with a tape

The scan is what apps built on Apple's RoomPlan framework do, FloorQuote among them: walk the room, and the phone returns a floor plan with each wall, door and window in place, so the area and the perimeter come from the shape instead of from a sketch on the back of a box.

Which iPhones have LiDAR

Every iPhone Pro and Pro Max from the iPhone 12 Pro onward — the 12 Pro, 13 Pro, 14 Pro, 15 Pro, 16 Pro and 17 Pro generations. The standard, Plus, Air, mini, SE and "e" iPhones do not have it.

To check yours: look at the camera bump. The LiDAR scanner is the small dark circle beside the lenses, on the Pro models only.

Measuring for flooring with the Measure app

Measure at floor levelWalls are rarely plumb and baseboards stick out. Measure wall to wall along the floor, not at chest height where the phone is comfortable.
Take the longest length and the widest widthFloors are ordered to cover the room at its biggest, not its average. Measure both ends of the room and keep the larger number.
Break odd shapes into rectanglesAn L-shaped room is two rectangles. A bay, a closet or a hearth cut-out is its own row. Add the rectangles, subtract the cut-outs.
Run into the doorwaysFlooring stops under the door, where the transition strip sits — measure to the middle of the threshold, not to the frame.
Measure everything twiceAR measurements drift when the phone moves too fast or the floor has no texture to lock onto. If two tries disagree by more than an inch or two, do it a third time.

Then the arithmetic: length × width for each rectangle, added up. The flooring calculator does it room by room and adds the waste your laying pattern needs.

Getting a clean LiDAR scan

Light the room. Open the curtains and switch the lights on. Scans lose walls in the dark.
Move slowly and keep the floor edges in view. Walk the perimeter, pointing the phone at where the walls meet the floor. That line is the part a flooring quote depends on.
Open the doors. A closed door reads as wall, and the closet behind it disappears from the area.
Watch mirrors and glass. They confuse any depth sensor. A mirrored wardrobe door can add a room that is not there.
Scan closets and bays on their own if the first pass missed them, and check the room count before you leave.

How accurate is it?

Apple does not publish an accuracy figure for room scans, so treat any exact claim you see with caution. In practice a scan is good enough to order flooring and not good enough to cut a scribe. The quick way to know whether to trust a particular scan is to tape one wall and compare: if the tape and the scan agree, the rest of the room is worth believing.

What no phone can see from above the floor: what is under the cabinets and appliances, whether the subfloor is level and dry, and the stairs — stairs are counted by the piece, not by area.

From a scan to a quote

FloorQuote is built on this: scan the room with the LiDAR scanner, check the measurements, pick the product out of your own price book, and it prints an itemised quote with your company at the top. On an iPhone without LiDAR you can still type each room's area and perimeter in by hand and quote it the same way.

Get FloorQuote on the App Store Work out the boxes

Last reviewed 22 September 2026