Measure Tools turns your phone camera into a complete measuring kit: point-to-point AR measurements, heights, areas, angles, chained runs, a DPI-calibrated onscreen ruler, and a bubble level — on iOS and Android, free to download.
An AR (augmented reality) measuring app uses your phone's camera and motion sensors to understand the space in front of you. As you move the phone, the app tracks visual features in the camera image and builds a live model of the surfaces around you — floors, walls, tabletops. When you tap the screen, it places a measurement point at a real position in that space, and the distance between two points becomes a measurement you can read right on the camera view.
In practice, that means you aim the target at the center of the screen at the start of what you want to measure, tap anywhere to set the point, aim at the end and tap again — and the measurement appears as an overlay on the real scene. (Aiming with a crosshair instead of tapping on the spot is deliberate: a fingertip covers an area of the screen, so tapping directly on the target would be far less precise.) No tape measure, no second pair of hands, and no writing numbers on the back of your hand. People search for this category under many names — augmented reality ruler, virtual ruler app, camera ruler app — but they all describe the same idea: measuring the real world through your phone's camera.
Where apps differ is in how much they do beyond a single straight line. A basic AR ruler stops at point-to-point distance. Measure Tools is built as a full toolkit, which is what the rest of this page covers.
Measure Tools ships with a whole set of measuring modes, each tuned for a specific job:
Point-to-point measurement — the classic AR ruler: set two points on any
surface with the center target and read the distance between them.
Height measurement — measure vertical distances such as ceiling heights,
door frames, or how tall a wardrobe is, without climbing anything.
Floor and horizontal measurements — measure runs along the floor or across a
wall, ideal for room dimensions and furniture footprints.
Chain measurement — tap a sequence of points and measure each segment in one
continuous chain, useful for walls with corners or L-shaped runs.
Angles — measure the angle between surfaces or edges, handy for sloped
ceilings, stair runs, and awkward corners.
Rectangle mode — measure rectangular shapes like windows, doors, TV screens,
and tabletops in a purpose-built mode instead of stitching four separate lines together.
3D Box Preview — preview a 3D box at real size in your space, so you can see
whether something of a given size will actually fit before it arrives.
Cylinder preview — the round counterpart to the 3D box: preview a true-size
cylinder in your space for round tables, plant pots, lamps, and anything else without corners.
Both the box and cylinder previews are included with the Measurements subscription.
Virtual wall mode — place a virtual wall in your room by tapping along a floor
edge and raising the phone to set its height. Great for visualizing partitions or checking
sight lines. Virtual wall mode is included with the Measurements subscription.How the plans work: Measure Tools is free to download, with free tools and premium subscriptions. The Measurements subscription unlocks every measuring mode — including the 3D Box and Cylinder previews plus Virtual Wall and Rectangle modes — and unlimited measurement folders. The 3D Planning subscription includes everything in Measurements and adds floor plans and unrestricted custom real-size furniture. You can try it free before subscribing.
Sometimes you don't need augmented reality at all — you need a ruler, right now, for something small enough to hold against your phone. That is exactly what people mean when they search for a camera ruler app, virtual ruler app, or ruler camera app, and Measure Tools covers it with a dedicated onscreen ruler.
The onscreen ruler is DPI-calibrated to your specific device, so the markings on the screen correspond to real millimeters and inches. It comes in two forms:
Because it measures against the physical screen rather than through the camera, the onscreen ruler doesn't depend on lighting, surface texture, or AR tracking — it's the most direct way to measure small objects with a phone.
Alongside it, Measure Tools also includes a bubble level that uses your device's motion sensors. It switches between a flat mode (phone lying on a surface, for leveling tables and shelves) and an edge mode (phone held on its edge, for checking picture frames and mounting rails). Both the onscreen ruler and the bubble level run directly on the home screen — no camera session required.
Beyond measuring, the premium 3D Planning tier adds floor plans and custom real-size furniture — place true-size pieces in the actual room and walk around the layout before buying anything. Read more in our floor plan app guide and our guide to measuring furniture before you buy.
AR measurement is genuinely useful, but it's fair to be clear about what it is and isn't. AR measuring works by tracking the camera image, and its accuracy depends on real-world conditions: lighting, how much visible texture the surface has, and how steadily you move the phone. On well-lit, textured surfaces with careful taps, results are typically close enough for planning, shopping, and estimating. On glossy, dark, or featureless surfaces, or with rushed movement, accuracy degrades. (Our guide to AR accuracy explains every failure cause — and the fix for each.)
Our recommendation is simple: use Measure Tools for estimates, planning, and checking whether things fit. For anything where precision is critical — cutting materials, ordering custom-made items, building code compliance — verify the final numbers with a tape measure or laser measure before you commit. An AR measuring app replaces a lot of tape-measure moments, but it is not a substitute for verified precision where mistakes are expensive.
Searching for an AR measuring app for iPhone specifically? Measure Tools runs on both platforms, and the hardware you use does affect results:
If you're weighing up which AR measuring app to install, the honest way to decide is by what you actually need to do. If it's one straight line, most apps — including the built-in ones — will manage. If you measure rooms, plan furniture, need heights and angles, want a real onscreen ruler and bubble level in the same app, and want your measurements saved as photos you can revisit, that's the job Measure Tools is built for. It's one toolkit, on both iOS and Android — and if the name "AR Ruler" rings a bell, that was us: the app was listed for years as "Measure Tools - AR Ruler" before becoming "Measure Tools - AR Room Planner" as the toolset outgrew the label. It has been in continuous development since 2017, built by a team working in augmented reality since 2013.
Try it on your own wall: download the app, measure something you already know the size of, and judge the results in your actual lighting on your actual phone. That five-minute test tells you more than any ratings screenshot.
An AR ruler measures through the camera: it places points in 3D space, so it handles rooms, walls and furniture at any distance. An onscreen ruler is the opposite end of the scale — real, DPI-calibrated markings drawn on the display, for small objects you hold against the glass. No camera, no tracking, no lighting requirements. Measure Tools includes both, and the onscreen ruler is free.
Yes — that's what the dedicated vertical mode is for. Aim at the floor, then at the ceiling, and the app measures the height in AR: no ladder and no second person. The same mode handles door frames, wardrobes, and anything else vertical.
The core measuring tool is free with no limit on how much you measure, and the bubble level and DPI-calibrated onscreen ruler are free too (the free experience is ad-supported, with two folders for saved measurements). Subscriptions unlock the additional modes — Rectangle, Virtual Wall, the 3D Box and Cylinder previews — plus unlimited measurement folders, floor plans and true-size furniture planning.
Free to download on iPhone, iPad, and Android — you can be measuring your first wall two minutes from now.
Measure Tools - AR Room Planner