USDZ vs OBJ vs RoomPlan JSON: 3D Scan File Formats Explained

After a LiDAR scan, you often want to use it somewhere else: on a client's iPhone, in a CAD program, in Blender or in your own script. Three file formats come up again and again: USDZ, OBJ and RoomPlan JSON. This guide explains which one you need for which task. Choosing the wrong format is rarely a disaster, but it can mean an extra conversion step, a model that does not open where you need it, or the loss of the structured data that made the scan useful.

In short, the three formats describe the same room in three fundamentally different ways. USDZ is a finished 3D scene for viewing and AR. OBJ is a raw mesh for editing. RoomPlan JSON is the underlying data, the parametric description of the room. LiDAR Room Scanner exports USDZ and RoomPlan JSON directly; OBJ is one conversion step away when a tool requires it. With this distinction in mind, the choice becomes simple.

The Big Picture: Scene, Mesh, and Data

Before going through the formats one by one, it helps to know what an iPhone LiDAR scan actually produces.

When you scan a room with LiDAR Room Scanner, Apple's RoomPlan does more than capture a point cloud. It recognizes walls, doors, windows, openings and furniture as separate objects with dimensions and positions. This semantic information is the reason why the three formats differ so much:

• USDZ packages the result as a 3D scene you can view: geometry plus materials, ready to place in AR or open in design software. Room scans export as a parametric USDZ; Object Capture models export as a textured USDZ.
• OBJ is a raw surface mesh (triangles, optionally with a photo texture) for editing, sculpting or remeshing. LiDAR Room Scanner does not write OBJ itself, but a USDZ converts to OBJ in a few steps.
• RoomPlan JSON contains the parametric data itself, the list of walls and objects with their measurements, so the scan can be re-imported, analyzed or rebuilt in software.

The same scan, described in three ways. The following sections explain when to use which.

USDZ: The AR and Presentation Format

USDZ is Apple's 3D format, based on Pixar's Universal Scene Description (USD). If you have tapped a 3D model link on an iPhone and seen the model appear on your floor through the camera, that was USDZ and AR Quick Look. A USDZ file is a single compressed archive that bundles geometry, materials and textures.

For room scans, LiDAR Room Scanner creates a parametric USDZ: a clean scene in which walls, openings and furniture are organized as recognizable elements rather than an unstructured mass of triangles. This structure makes further work easier. Object Capture models are exported as a textured USDZ instead: a detailed mesh with the photographed surface colors.

Where USDZ works well

USDZ's main strength is native support for AR and viewing on Apple devices:

• AR Quick Look: Tap a USDZ file in Safari, Messages, Mail or Files and it opens in AR, so you can place the scanned room or object in real space without an extra app. This is useful for showing a client a captured space on their own iPhone.
• Reality Composer: Build AR scenes with your USDZ scan as a component.
• 3D software with USD support: Tools such as Blender import USDZ, so a scanned room can serve as the starting point for further 3D work. Support in CAD and BIM software such as SketchUp, Rhino or Revit depends on the version and often requires a plugin, so check your software before relying on it.
• macOS Quick Look: Press the space bar on a USDZ file in Finder to preview the 3D scene.

Because the USDZ from a room scan is parametric and well organized, it arrives in these tools as a room with walls and openings rather than a mesh you have to interpret.

USDZ trade-offs

The main limitation is where it fits. USDZ works best in Apple and design contexts; it is not the universal mesh-editing format that OBJ is, and it does not contain the structured data that JSON does. If your next step is extensive mesh editing in a sculpting tool, or passing measurements to a script, USDZ is not the most direct route. For viewing, presenting and importing into 3D software, it is the first format to use.

RoomPlan JSON: The Data Format

This format is easy to overlook, but for the right task it is the most useful of the three. RoomPlan JSON is not a 3D model you look at. It is the parametric description of the room as structured data: walls, doors, windows, openings and detected objects, each with dimensions, position and relationships, in plain JSON.

Why parametric data matters

A mesh tells you where the surfaces are. RoomPlan JSON tells you what the room consists of. That makes things possible that a mesh cannot do:

• Re-import and rebuild: Because the JSON describes the room parametrically, the scan can be imported and reconstructed, with walls as walls rather than fixed triangles. LiDAR Room Scanner can import RoomPlan JSON into your scan library, so your scans remain portable data rather than one-way exports.
• Portability and your own workflows: JSON can be read by practically every programming language, tool and database. If you build a workflow, such as passing room dimensions to a space planning system, filling a property database or running your own analysis, the JSON is the clean, machine-readable source.
• Future use: A mesh is a snapshot of the geometry; the parametric data is the model itself. If you keep the JSON, you can generate plans, models or measurements again later.

RoomPlan JSON trade-offs

The downside is that JSON is not a viewable model. If you send it to a client with AirDrop, they will see code, not their living room. It is the format for systems and workflows, not for presentation. Think of it as the master record you keep, from which the viewable formats are derived. RoomPlan JSON export is free; importing a scan into your library is a Pro feature. See pricing for details.

OBJ and the Textured Mesh: The Editing Format

OBJ is one of the oldest 3D formats still in wide use. Wavefront created it in the 1980s, and almost every 3D application supports it. Its advantage is simplicity and wide support: if a tool works with 3D geometry, it reads OBJ.

LiDAR Room Scanner does not export OBJ directly, and a room scan does not produce a textured mesh at all, because RoomPlan describes the room parametrically. Textured meshes come from Object Capture, the guided photo capture for single objects, and the app saves them as textured USDZ, which keeps the geometry and the photo textures together in one file. When a tool requires OBJ, import the USDZ into Blender, whose USD importer reads USDZ archives including textures, and export it via File › Export › Wavefront (.obj).

Where the textured mesh works well

• Mesh editing and cleanup: Import into Blender (free and open source), Maya, 3ds Max, ZBrush or Cinema 4D to retopologize, decimate, sculpt or repair the geometry. OBJ imports into all of them.
• Capturing the real surface: When you need the actual surface, for example as a textured record of an object or a heritage piece, the mesh preserves what was really there instead of an idealized reconstruction.
• Object Capture workflows: The textured models from Object Capture belong in the mesh world, where OBJ is the common exchange format for editing and finishing. Convert the USDZ and continue there.

Textured mesh trade-offs

A mesh has no knowledge of structure: it knows where a surface is, but not that the surface is a wall. You lose the parametric structure, so you cannot easily derive a floor plan or exact dimensions from it as you can from the JSON. OBJ also usually consists of several files (the .obj geometry, a material file and texture images), so keep them together. Use the mesh when you want to edit the geometry; use USDZ or JSON when you need structure.

Side-by-Side Comparison

Which One Should You Pick?

Choose the format based on your next step, not on a general sense of which one is best.

You want to show someone the space in AR, or continue in 3D software. Choose USDZ. It opens in AR Quick Look with a tap and arrives in USD-capable software as an organized scene.

You are building a workflow, filling a database, or want to keep the master record so you can re-import or regenerate later. Choose RoomPlan JSON. It is the structured, portable, machine-readable source, and LiDAR Room Scanner can import it again.

You need to edit, remesh, repair or sculpt the geometry, or you captured an object with Object Capture. Start with the textured USDZ and convert it to OBJ in Blender when your editing tool needs it. OBJ is the format almost every 3D editing tool reads.

You are not sure and want to keep your options open. Export more than one. The scan is the same; the formats are different views of it. A common approach is to keep the RoomPlan JSON as the archive copy, share the USDZ as an AR preview for the client, and convert to OBJ only when a specific edit requires it. If your scans are meant for 2D drawings instead of 3D, see how to export iPhone floor plans to CAD for the DXF, PDF and SVG exports.

How to Export from LiDAR Room Scanner

The export works the same way for every format:

1. Scan your room or object. Use RoomPlan capture with on-screen guidance for a room, or the guided Object Capture for a single object. If you are new to it, how to scan a room in 3D with iPhone LiDAR covers the basics of capturing, and the scanning tips guide explains how to get clean, accurate results.
2. Open the scan in your library. Every scan is saved on the device and can be browsed, renamed and exported again at any time.
3. Choose the format you need: the USDZ model or the RoomPlan JSON data for a room scan, the textured USDZ for an Object Capture model.
4. Send it via the iOS share sheet. Send it to your Mac with AirDrop, save it to Files, email it or open it in another app.

Everything is processed on the device: your scans stay private, and the export works offline without an upload. Both capture modes and USDZ and RoomPlan JSON export are free; sharing floor plan exports (DXF, PDF, SVG, PNG and CSV), GPS data in exports and importing scans are part of Pro. The pricing page has the full overview, and how it works shows the workflow from capture to export.

The Short Version

Three formats, three tasks. USDZ is the finished scene you show people and import into 3D software. RoomPlan JSON is the parametric data you keep, re-import and pass to other systems. OBJ is the raw geometry you edit, one Blender conversion away from the USDZ. The three formats do not compete; they carry the same scan to different destinations, and the right choice depends on where the scan goes next. The feature set shows how capture, the floor plan editor and these exports fit together.

If you want to scan a room once and get both an AR-ready USDZ and the underlying RoomPlan data, download LiDAR Room Scanner from the App Store.