3D Model File Formats: Types, Extensions, Use Cases [& More]

TL;DR Every 3D file format is optimized for a specific job: STL and 3MF for 3D printing, glTF and USDZ for web and AR, FBX and OBJ for animation and game pipelines, STEP and IGES for precision CAD, and USD for complex multi-tool production workflows. Understanding the differences between these 3D model formats — their extensions, what data they store, and where they're supported — is the fastest way to avoid compatibility issues and wasted rework. This guide covers the most widely used 3D model file types, what they store, and how to pick the right one for your project. If you need to convert between formats, Meshy's free 3D file converter handles the most common pairs.

3D file formats are standardized ways to store three-dimensional model data, including geometry, textures, animation, and metadata, and are used across different software and workflows. With so many types of 3D file formats available, it's not always clear which one is right for your project. Each format serves a unique purpose, and choosing the wrong one can cost you compatibility, quality, or hours of rework.

Whether you're working with 3D print file types, exploring animation pipelines, or just getting started with different types of 3D modeling, this guide walks you through the most important 3D model file format types — their extensions, what they store, and how to choose the right one for your needs.

Quick Reference: 3D File Format Comparison — Extensions, Features & Use Cases

Size estimates: Small = typically under 10 MB, Medium = 10–100 MB, Large = 100 MB+ for equivalent geometry complexity. Actual file sizes vary based on model detail, polygon count, and embedded textures.

Which 3D File Formats Work Best for 3D Printing?

3D print file types need to describe surface geometry accurately so a slicer can compute toolpaths. Color and material support varies widely by format. See our full 3D print file type guide and 3D printing guide for deeper coverage.

STL

• File extension: .STL
• Internet media type: model/stl, model/x.stl-ascii, model/x.stl-binary

STereoLithography (STL) is the oldest and most widely supported 3D printing format. It represents surfaces as a mesh of triangles — no color, texture, material, or unit data is stored. Virtually every slicer (Cura, PrusaSlicer, Bambu Studio) and 3D modeling tool supports it, making it the default choice for FDM, SLA, and SLS workflows.

Key technical features:

• Encodes surface geometry as a list of triangles with outward-facing normals
• Binary STL is compact; ASCII STL is human-readable but larger
• Requires watertight (manifold) geometry to print correctly

Pros:

• Universal support across slicers, printers, and modeling tools
• Simple structure; easy to generate and parse programmatically

Cons:

• No color, material, or unit data
• Large files for high-polygon models
• No native support for multiple shells or internal structures

3MF

• File extension: .3mf
• Internet media type: application/vnd.ms-package.3dmanufacturing-3dmodel+xml, application/vnd.ms-printing.printticket+xml, model/3mf

3D Manufacturing Format (3MF) was developed by the 3MF Consortium (Microsoft, Ultimaker, Prusa, and others) as a modern alternative to STL. It's increasingly preferred in professional and multi-material workflows, with native support in PrusaSlicer, Bambu Studio, and Windows 3D Builder.

Key technical features:

• XML-based package storing geometry, color, materials, texture maps, print settings, and units
• Supports multi-material and full-color printing natively
• Encodes build orientation and support hints

Pros:

• Rich metadata: colors, materials, scale, and print settings in one file
• More compact than STL for equivalent geometry
• Actively developed; better suited for next-generation printers

Cons:

• Less universally supported than STL, especially on older or budget hardware
• Overkill for simple single-material prints

AMF

• File extension: .amf
• Internet media type: application/amf+xml

Additive Manufacturing File Format (AMF) is an ISO/ASTM international standard (ISO/ASTM 52915) developed as a direct successor to STL. Like 3MF, it addresses STL's core limitations by adding native support for color, materials, and curved geometry — but it has seen slower adoption than 3MF in practice.

Key technical features:

• XML-based format storing geometry, color, material, and texture data
• Supports curved triangles (higher-order surface approximation) for smoother output
• Encodes unit data and author metadata natively

Pros:

• Open international standard; no proprietary lock-in
• Native color and multi-material support, better geometry accuracy than STL
• Supported by Cura, PrusaSlicer, and several CAD tools

Cons:

• Largely superseded by 3MF in modern printing workflows — less tooling support
• Curved triangle support is rarely leveraged in practice
• Not as actively developed or promoted as 3MF

STL vs AMF vs 3MF: STL is universal but carries no color or unit data. AMF improved on STL but arrived before the ecosystem was ready. 3MF, backed by a major industry consortium, has since become the preferred modern alternative for professional print workflows.

Which 3D File Formats Work Best for Web, AR, and VR?

Web and AR/VR file formats need to balance visual fidelity with fast load times and real-time rendering performance. Physics-based rendering (PBR) material support is increasingly expected. This section covers glTF/GLB and PLY — for Apple ecosystem AR (iOS Quick Look, Vision Pro), see USDZ in Cross-Application Workflows below.

glTF / GLB

• File extension: .gltf, .glb
• Internet media type: model/gltf+json, model/gltf-binary

Graphics Language Transmission Format (glTF) is an open standard developed by the Khronos Group, sometimes called the "JPEG of 3D" for its ubiquity on the web. GLB is its binary-packed variant. It's the dominant format for WebGL applications, Three.js scenes, AR experiences on Android, and is the standard export format for AI 3D generation tools like Meshy.

Key technical features:

• Stores geometry, PBR materials, textures, skeletal animations, and scene hierarchy
• GLB packages all assets (including textures) into a single binary file
• Supports extensions for advanced features like transmission, clearcoat, and KTX2 compressed textures
• Designed for GPU-efficient delivery — minimal runtime processing needed

Pros:

• Extremely compact; loads fast in browsers
• Wide support across engines (Babylon.js, Three.js, Unity, Unreal)
• Actively maintained open standard with growing extension ecosystem

Cons:

• Less suited for offline DCC (digital content creation) workflows
• Some advanced material features require non-universal extensions

PLY

• File extension: .ply
• Internet media type: text/plain

Polygon File Format (PLY) was developed at Stanford for storing 3D scan and point cloud data. It can encode per-vertex color, normals, and arbitrary custom properties alongside geometry, making it a common output format for photogrammetry tools, LiDAR scanners, and NeRF pipelines.

Key technical features:

• Stores vertex and face data with arbitrary per-element properties
• Binary and ASCII variants available
• Natively supports point clouds without face data

Pros:

• Flexible structure; can store any per-vertex attribute
• Common output from scanning hardware and reconstruction pipelines
• Readable by most research and visualization tools (MeshLab, CloudCompare, Open3D)

Cons:

• No animation or material system
• Not suitable for real-time rendering without conversion
• Limited support in consumer tools and game engines

Note: For iOS and Apple ecosystem AR experiences, see USDZ in the Cross-Application Workflows section below — it's Apple's native AR format for Quick Look and Vision Pro.

VRML

• File extension: .wrl
• Internet media type: model/vrml, x-world/x-vrml

Virtual Reality Modeling Language (VRML) was the first widely adopted standard for 3D content on the web, developed in the mid-1990s and standardized as ISO/IEC 14772. It allowed interactive 3D scenes to be embedded in web browsers via plugins. While largely superseded by WebGL and glTF, VRML files still appear in legacy archives, older engineering exports, and some educational platforms. Its successor, X3D, extended the standard but also remains niche.

Key technical features:

• Human-readable text format describing 3D geometry, lighting, animation, and interactivity
• Supports scripting for interactive behaviors
• Scene graph structure with nodes and routes

Pros:

• Historically significant; large archive of legacy content
• Still supported in some CAD tools (CATIA, SolidWorks) as an export option
• Human-readable; relatively easy to inspect manually

Cons:

• Requires plugins or dedicated viewers in modern browsers — no native browser support
• Poor performance compared to modern GPU-optimized formats like glTF
• Effectively a legacy format; new projects should use glTF/GLB instead

Which 3D File Formats Work Best for Animation, Film, and Game Development?

Animation and game formats need to carry full scene data — geometry, rigging, skinning, blend shapes, and materials — across different DCC tools and engines. For a deeper look at game-specific workflows, see our guide to 3D modeling for games. Interoperability between tools like Maya, Blender, and Unreal is the primary concern.

FBX

• File extension: .fbx
• Internet media type: application/octet-stream

Filmbox (FBX) was originally developed by Kaydara and is now maintained by Autodesk. It has become the de facto standard for transferring animated 3D assets between DCC tools and game engines — serving as the default exchange format between Maya and 3ds Max and engines like Unity and Unreal Engine, and widely used in motion capture and VFX pipelines.

Key technical features:

• Stores meshes, bones, skinning weights, morph targets, cameras, lights, and animation curves
• Binary and ASCII variants (binary is more common)
• Supports multiple animation takes in a single file
• Proprietary format owned by Autodesk; no public spec

Pros:

• Near-universal support across 3D tools and game engines
• Handles complex rigs, blend shapes, and multi-layer animations reliably
• Carries cameras and lights for full scene transfers

Cons:

• Closed, proprietary format — no public specification
• Version incompatibilities between Autodesk SDK versions are common
• Large file sizes compared to glTF

DAE (Collada)

• File extension: .dae
• Internet media type: model/vnd.collada+xml

Collaborative Design Activity (Collada), developed by the Khronos Group and standardized as ISO/PAS 17506, was designed as an open, cross-application interchange format for DCC tools. It predates glTF and served as the primary open alternative to FBX for many years. While largely displaced by glTF in real-time and web contexts, DAE remains a common export target in tools like Blender, SketchUp, Maya, and Cinema 4D, and is the native format used in Google Earth and some game engines.

Key technical features:

• XML-based format storing geometry, materials, animation, physics, and scene hierarchy
• Supports skinning, morph targets, and multi-layer animation
• Designed to be tool-agnostic with no vendor lock-in

Pros:

• Open standard; no proprietary restrictions
• Wide support across DCC tools and some game engines (Unity, Godot)
• Handles full scene data including physics definitions

Cons:

• Verbose XML leads to large file sizes; slower to parse than binary formats
• Inconsistent implementation across tools — round-trip fidelity varies
• Largely superseded by glTF for real-time and by FBX for production pipelines

3DS

• File extension: .3ds
• Internet media type: image/x-3ds, application/x-3ds

The 3DS format is the original binary file format of Autodesk 3ds Max (formerly 3D Studio DOS), widely used throughout the 1990s and early 2000s. It carries geometry, basic materials, and limited animation data. While 3ds Max itself now uses the newer .max format, .3ds remains prevalent in legacy content libraries and is still accepted by many modern tools as an import format.

Key technical features:

• Binary chunk-based format storing meshes, lights, cameras, and basic keyframe animation
• Material definitions include diffuse, specular, and opacity maps
• Vertex count per mesh capped at 65,536 (a common pain point)

Pros:

• Widely supported as an import format across DCC tools, game engines, and viewers
• Compact binary structure; relatively small file sizes
• Large legacy asset libraries available in this format

Cons:

• Hard limit of 65,536 vertices per mesh — problematic for high-poly models
• No support for modern PBR materials or skeletal animation
• Effectively a legacy format; FBX or glTF are preferred for new work

OBJ

• File extension: .obj
• Internet media type: model/obj

Wavefront OBJ is one of the oldest 3D interchange formats, originally developed for the Wavefront Advanced Visualizer in the 1980s. It stores static geometry and references an external .mtl file for basic material definitions. Despite its age, it remains widely used for simple model exchange where animation is not required.

Key technical features:

• Plain text format storing vertices, faces, normals, and UV coordinates
• Materials defined in a separate .mtl file referencing texture maps
• No support for animation, rigging, or scene hierarchy

Pros:

• Near-universal support across DCC tools, game engines, and online platforms
• Human-readable and easy to parse programmatically
• Simple structure; reliable for basic geometry exchange

Cons:

• No animation support
• Material system is limited; no PBR support natively
• Larger file sizes than binary formats for equivalent geometry

BLEND

• File extension: .blend
• Internet media type: application/x-blender

BLEND is the native project format of Blender, the open-source 3D creation suite. Unlike most interchange formats, .blend files store the entire Blender scene state — objects, meshes, materials, animations, modifiers, physics simulations, render settings, and scripting data. It is not designed for cross-application exchange, but its ubiquity in open-source and indie workflows makes it a commonly encountered format.

Key technical features:

• Binary format storing all Blender-internal data structures directly
• Version-dependent: files saved in one Blender version may behave differently when opened in another
• Supports linked and appended assets from other .blend files
• Can embed Python scripts and custom properties

Pros:

• Complete scene fidelity — no data loss when working entirely within Blender
• Free and open-source; no licensing restrictions
• Blender's growing adoption makes .blend increasingly common in pipeline discussions

Cons:

• Not cross-application: only Blender reads .blend natively (some tools offer limited import)
• Version compatibility issues between major Blender releases
• Not suitable for delivery or exchange with non-Blender pipelines — export to FBX, glTF, or OBJ instead

Which 3D File Formats Work Best for Voxel Art and Games?

Voxel formats represent 3D objects as a grid of discrete cubic units (voxels) rather than as polygonal meshes. This makes them conceptually similar to 3D pixels — well-suited for a specific aesthetic and workflow, but not interchangeable with mesh-based formats without conversion.

VOX

• File extension: .vox
• Internet media type: N/A (no registered MIME type)

MagicaVoxel's .vox format has become the de facto standard for voxel art assets, driven by the popularity of the free MagicaVoxel editor. It stores voxel grid data alongside a color palette, and is supported by a growing ecosystem of voxel editors (Qubicle, VoxEdit), game engines (Unity via plugins, Godot natively), and 3D printing workflows.

Key technical features:

• Stores voxel grid(s) with per-voxel palette color index
• Supports multiple named models within a single file
• RIFF-like chunk-based binary format; compact and fast to parse
• Limited animation support via frame sequences in newer spec versions

Pros:

• Compact file sizes for complex voxel scenes
• Wide support in voxel authoring tools and growing game engine support
• Well-suited for 3D printing (voxel-to-mesh conversion is straightforward)
• Large community; abundant free assets available

Cons:

• Voxel-specific: not interchangeable with mesh workflows without explicit conversion
• Limited animation capabilities compared to skeletal animation in mesh formats
• No standard MIME type; handling varies by platform

Note: VOX files need to be converted to mesh formats (OBJ, glTF, FBX) for use in most game engines and rendering pipelines. Tools like MagicaVoxel, Blender (via plugin), and online converters handle this step.

Which 3D File Formats Work Best for CAD and Engineering?

Among all the types of 3D file formats, CAD formats are unique in prioritizing geometric precision over rendering performance. Unlike mesh-based formats, engineering formats typically store parametric or B-rep (boundary representation) geometry that can be re-edited and manufactured to exact tolerances.

STEP

• File extension: .stp, .step
• Internet media type: model/step

Standard for the Exchange of Product model data (STEP) is an ISO international standard (ISO 10303) and the primary format for exchanging precise CAD geometry between different software packages. It is supported by virtually every professional CAD application including CATIA, SolidWorks, Fusion 360, and FreeCAD.

Key technical features:

• Stores B-rep geometry with exact mathematical surface definitions
• Preserves assembly structure, part relationships, and metadata
• Human-readable text format (.stp / .step)

Pros:

• Vendor-neutral open standard; no proprietary lock-in
• Preserves design intent and editability across different CAD systems
• Supports complex assemblies with part hierarchy

Cons:

• Not suitable for rendering or real-time visualization without conversion to a mesh
• Large files for complex assemblies
• Slow to import in some applications due to B-rep reconstruction

IGES

• File extension: .igs, .iges
• Internet media type: model/iges, model/vnd.igs

Initial Graphics Exchange Specification (IGES) is an older US national standard (ANSI) for CAD data exchange, predating STEP by several years. It remains in use largely for compatibility with legacy systems and older manufacturing workflows.

Key technical features:

• Supports wireframe, surface, and solid geometry
• Text-based; widely readable across old and new systems
• Less structured than STEP; prone to translation errors

Pros:

• Near-universal support on legacy systems
• Acceptable for surface and wireframe data exchange

Cons:

• Older standard; more translation errors than STEP
• Limited metadata and assembly structure support
• Generally superseded by STEP for new workflows

DWG

• File extension: .dwg
• Internet media type: image/vnd.dwg, application/acad

Drawing (DWG) is Autodesk's proprietary native file format for AutoCAD, and the most widely used format in architecture, construction, and engineering drafting workflows globally. While DXF is AutoCAD's open exchange format, DWG is the format practitioners actually work in day-to-day — most CAD files shared in AEC (Architecture, Engineering, and Construction) industries arrive as .dwg files.

Key technical features:

• Binary format storing 2D and 3D geometry, layers, blocks, annotations, and metadata
• Supports both 2D drafting and 3D solid/surface modeling (though primarily used for 2D)
• Version-dependent: AutoCAD releases a new DWG version approximately every 3 years

Pros:

• Industry standard in AEC; expected by architects, engineers, and contractors
• Rich annotation and layer support for technical drawings
• Supported by AutoCAD, BricsCAD, DraftSight, Revit (import), and many others via the Open Design Alliance (ODA) libraries

Cons:

• Proprietary format owned by Autodesk; non-Autodesk tools rely on reverse-engineered or licensed readers
• Version compatibility issues — newer DWG versions may not open correctly in older software
• Not suitable for rendering, animation, or 3D printing without conversion
• For open exchange of the same content, DXF is preferred

DWG vs DXF: DWG is Autodesk's native binary format; DXF is its text-based open exchange counterpart. DWG is what professionals work in; DXF is what they share with tools that don't support DWG directly.

DXF

• File extension: .dxf
• Internet media type: image/vnd.dxf

Drawing Exchange Format (DXF) is an Autodesk-developed format primarily used for 2D technical drawings and CAD data exchange. While it can represent 3D geometry, it is most commonly used for 2D floorplans, CNC toolpaths, and laser cutting files.

Key technical features:

• Stores 2D and basic 3D geometry (lines, arcs, splines, meshes)
• Text-based format; widely supported across CAD and manufacturing tools
• No material, texture, or animation support

Pros:

• Near-universal support in CAD, CNC, and laser cutting software
• Good for 2D-to-3D workflow handoffs

Cons:

• Limited 3D capability compared to STEP or OBJ
• Not suitable for rendering, animation, or 3D printing
• Version compatibility issues between Autodesk releases

Which 3D File Formats Work for Cross-Application Workflows?

USD-based formats are designed to handle the complexity of large-scale 3D pipelines where multiple tools, teams, and asset types need to work together. Unlike single-asset formats, USD describes entire scenes with layering, referencing, and collaboration built in.

USD / USDZ

• File extension: .usd, .usda, .usdc, .usdz
• Internet media type: model/vnd.usdz+zip

USD-based formats are designed to handle the complexity of large-scale 3D pipelines where multiple tools, teams, and asset types need to work together. Unlike single-asset formats, USD describes entire scenes with layering, referencing, and collaboration built in.

Key technical features:

• Layered composition system allows non-destructive overrides and collaborative editing
• Supports geometry, materials, animation, lighting, cameras, and physics in one scene graph
• USDZ is a zip-based single-file package used by Apple's AR Quick Look on iOS and macOS
• .usda is human-readable ASCII; .usdc is binary (crate format); .usdz is packaged

Pros:

• Handles scenes of arbitrary complexity; used in production-scale film pipelines
• Native support in Apple ecosystem (Reality Composer, AR Quick Look, Vision Pro)
• Adopted by NVIDIA Omniverse for industrial digital twins and simulation
• Open source with active development from Pixar, Apple, NVIDIA, and Adobe

Cons:

• Steep learning curve; the composition system is complex
• Tooling outside major DCC apps and engines is still maturing
• USDZ is read-only in most consumer tools; not suitable for editing workflows

How to Choose the Right 3D File Format Type for Your Project?

Choosing the right 3D model file types comes down to a few practical questions:

• What's the destination? — The end use is the most important factor — where the file needs to go largely determines the format. A 3D printer, a web browser, a game engine, and a CAD system each have formats purpose-built for them. Start here before considering anything else.
• Do you need animation? — If your model needs to move — characters, product configurators, AR objects — you need a format that supports skeletal animation and animation tracks. If not, simpler geometry-only formats may be sufficient.
• Do you need materials and textures? — Some formats embed full PBR material data; others reference external files or carry no material information at all. If visual fidelity matters, check what your format supports before exporting.
• Does file size matter? — For web delivery and real-time applications, load time directly affects user experience. For print and CAD workflows, size is less critical than geometric accuracy.
• What software is involved? — Not all formats survive the round-trip between tools without data loss. Always verify what your source application exports and what your target application reliably imports. Check which file extensions (.fbx, .gltf, .step, etc.) each tool supports before committing to a workflow.
• Do you need to convert? — If you're moving assets between pipelines, a dedicated converter will produce cleaner results than re-exporting from a DCC tool. Meshy's free 3D file converter supports direct conversion between STL, OBJ, FBX, glTF, and more — no software installation required.

FAQs

Which is better, STL or OBJ?

It depends on the task. STL is the standard for 3D printing because every slicer accepts it, but it carries no color or material data. OBJ supports materials (via .mtl) and is better for general modeling exchange. For anything other than printing, OBJ is more capable.

Is STL or STEP higher quality?

STEP is significantly higher quality for precision work. STEP stores mathematically exact NURBS geometry, while STL approximates curved surfaces with triangles. For engineering and manufacturing, always use STEP. STL is fine for most 3D printing workflows where exact curves are less critical.

What is the difference between DXF, OBJ, and STL?

DXF is a 2D/3D CAD interchange format from Autodesk, primarily for technical drawings and 2D geometry. OBJ is a general-purpose 3D mesh format that supports materials. STL is a 3D printing format that stores only surface triangles. They serve very different purposes and are not interchangeable.

Should I use OBJ or FBX?

Use FBX if your model has animation, a rig, blend shapes, or needs to carry camera and light data. Use OBJ for simple static geometry exchange — it's smaller and more universally readable. For modern game development workflows, glTF/GLB is often the better choice over both.

Is STL a 2D or 3D format?

STL is a 3D format. It encodes a 3D surface as a mesh of triangles in X/Y/Z space. It has no 2D mode.

Is glTF better than OBJ?

For most modern use cases, yes. glTF supports animations, PBR materials, and scene hierarchy in a single compact file, and it's the preferred format for web and real-time applications. OBJ is simpler and more universally supported for static geometry, but glTF is the better long-term choice.

Is 3MF better than OBJ?

They serve different purposes. 3MF is for 3D printing with color and material support. OBJ is for rendering and game pipelines. If you're printing multi-material or colored models, 3MF is the clear choice.

Is CAD a STL file?

No. CAD is a category of software and workflow (Computer-Aided Design), not a file format. CAD tools like SolidWorks and Fusion 360 can export to STL, but their native formats (STEP, IGES, proprietary) are different. STL is a mesh format derived from CAD geometry, not CAD itself.

What are the current industry standards for 3D file formats?

It varies by industry:

• Game development: FBX and glTF
• Film/VFX: USD and FBX
• 3D printing: STL and 3MF
• Engineering CAD: STEP
• Web and AR: glTF/GLB and USDZ
• USD is increasingly influential across multiple industries as a universal scene description standard.

What file formats do 3D design tools support?

It varies by tool, and most support multiple 3D model file types. Consumer tools like Tinkercad focus on STL and OBJ. DCC apps like Maya and Blender support FBX, OBJ, glTF, and USD. CAD tools prioritize STEP and IGES. Game engines like Unity and Unreal import FBX and glTF natively.

Which file formats should an AI 3D generator support for moving assets between Unity, Unreal and a web viewer?

Universal cross-engine format coverage:

1. GLB (glTF 2.0 binary) — best universal choice. Web viewers (model-viewer, three.js, Babylon.js), Unity (UnityGLTF/glTFast), Unreal (plugin), Godot (native). Single-file, PBR-ready, AR-compatible.
2. FBX — Unity (built-in), Unreal (built-in primary FBX path). For Maya/Max/MotionBuilder pipelines.
3. USDZ — iOS AR Quick Look. Required for native iOS AR.
4. For web — GLB with Draco compression.
5. For Unreal projects — FBX with embedded textures, or GLB via plugin.
6. For Unity — GLB via UnityGLTF/glTFast plugin (most modern), or FBX via built-in importer (legacy).
7. Animation support — FBX has the deepest animation support. GLB supports skeletal animation but is less mature for complex blend shape rigs.
8. Material parity — GLB's PBR (metallic-roughness) maps cleanly to Unreal's Lit and Unity's URP/HDRP Lit shaders.

Meshy ships GLB, FBX, OBJ, USDZ, STL, BLEND, and 3MF from a single generation. Pipeline standard: GLB as source of truth, FBX for studios with Maya/Max workflows, USDZ for iOS-specific AR. Test imports into your engine on a representative model before committing to a format choice.

How can I turn an image into an AR-ready 3D model with generative AI?

AR-ready means the model loads fast, looks right under real-world lighting, and ships in a format the AR runtime understands.

1. Generate via Meshy's Image-to-3D. For best results, select the Meshy-6 AI model.
2. Run Refine — closes holes and fixes non-manifold edges for a clean mesh. Then run Remesh for clean topology if you need LODs.
3. Reduce polycount where possible — AR runtimes (especially mobile) prefer 30–60K tris for hero objects, lower for catalog-scale.
4. Export USDZ for iOS Quick Look (Safari, Messages, native apps via ARKit) and GLB for Android Scene Viewer / WebXR / model-viewer.
5. Test under real lighting before publishing — AR Quick Look on an iPhone and Scene Viewer on an Android. Watch for transparent material edges, normal direction, and texture color cast.

Meshy ships USDZ and GLB from the same generation, so the same source asset feeds both iOS and Android AR without re-conversion.

Why does my exported .obj 3D model look wrong when opened in another program?

Common causes when an OBJ looks wrong in a different program:

1. Missing MTL — OBJ is geometry-only; materials live in a sidecar .mtl file. Make sure both .obj and .mtl ship together, plus the texture image files in the same folder. Meshy bundles these in the export zip.
2. Texture path issues — MTL references textures by relative path. If the texture isn't found, the model renders untextured. Check the path strings in the .mtl file.
3. Axis / orientation mismatch — Y-up vs Z-up varies by program. Blender uses Z-up; Maya, Unity, three.js use Y-up. The model may import rotated 90°. Fix on import (Blender: select "-Z forward, Y up" on import) or rotate after import.
4. Scale mismatch — units may differ between programs. Meshy exports at a sensible default; rescale on import to match your scene's unit system.
5. Normal direction — some programs interpret face normals differently. If the model looks inside-out, flip normals (Blender: Mesh → Normals → Recalculate Outside).
6. PBR materials lost — OBJ + MTL doesn't carry PBR by default. For PBR fidelity, use GLB instead.

Fix in order: GLB > FBX > OBJ for cross-program reliability. OBJ is universal but the most lossy.

Which tools let me iterate by editing the prompt while keeping the same base shape instead of regenerating from scratch?

This is exactly what Meshy's AI Texturing feature is built for. You generate the geometry once and iterate on prompts to repaint the surface without touching the mesh.

Workflow:

1. Generate the base mesh via Text-to-3D or Image-to-3D.
2. Run Refine to close holes and fix non-manifold edges, then Remesh for clean topology.
3. Open AI Texturing on the same mesh.
4. Iterate on the texture prompt — "weathered Viking warhammer, hand-forged iron, crimson rune carvings" → "polished ceremonial warhammer, gold filigree, gem inlays" → "sci-fi power warhammer, glowing blue energy lines, brushed steel." Each prompt produces a new PBR map set on the same geometry.
5. Pick the variant you want, export GLB / FBX with the new textures.

This pattern is dramatically cheaper and faster than regenerating geometry. It's how teams produce SKU variants for ecommerce, gameplay state variants (clean / damaged / burning), or art-direction explorations on a single base mesh. Meshy's UI keeps geometry constant by default when you re-texture; geometry only regenerates if you explicitly re-run Text-to-3D.

GLB vs USDZ vs FBX vs OBJ — which 3D file format should I use?

Pick by where the model is going:

• GLB — web, AR, and three.js. Single binary file, embeds geometry, textures, and PBR materials. Default for product viewers and engine pipelines that don't need rigged animations. Meshy's recommended general-purpose export.
• USDZ — iOS AR Quick Look (Apple's native AR format). Use when your target is the iOS Safari/Messages AR experience.
• FBX — game engines (Unity, Unreal) and DCC tools (Maya, 3ds Max) when you need rigged characters, skeletons, or animation tracks. Older but still the workhorse for animation.
• OBJ — universal mesh exchange. No animation, no embedded materials (uses a sidecar .mtl file), but every 3D app on earth opens it. Good fallback when GLB/FBX don't import cleanly.
• STL — 3D printing only. Geometry, no color, no UVs.
• 3MF — multicolor / multi-part 3D printing. Units-aware, multi-mesh assembly.
• BLEND — Blender-native; preserves materials, modifiers, and rigging perfectly.

Meshy exports all of these from a single generation. If you don't know yet, start with GLB.