STL to OBJ Converter

Turn a printable STL or a scan into an OBJ for Blender, Maya or ZBrush, in your browser.

Your file never leaves this browser. No account, no upload, no limit on how many you convert.

HOW IT WORKS

How to Convert an STL File to OBJ

Pick the STL, check what the browser read, download the OBJ.

  1. Open the STL

    Choose a printable model or scan no larger than 100 MB.

    Processed on your device

  2. Check mesh dimensions

    Inspect triangle count, object count and bounding box before export.

    Coordinate values remain equal

  3. Download the OBJ

    Save the same triangle geometry in OBJ form for your modelling application.

    Triangles remain triangles

What People Do With an OBJ Next

An STL moved into OBJ usually goes to one of these jobs in modelling software. These are the common next steps for the converted file.

Build Cleaner Retopology

You use the OBJ as a reference while rebuilding the model with deliberate edge flow.

Generate a model from a photo

Sculpt Surface Detail

You bring the mesh into a sculpting application to add folds, wear or fine forms.

OBJ to STL converter

Create UV Layouts

You unwrap the geometry and prepare texture coordinates inside your modelling software.

Describe a model in words

Prepare a Game Asset

You optimise the mesh, add UVs and build materials for use in a game project.

GLB to STL converter

Render Product Images

You place the object in a lit scene and create stills or turntable renders.

3D model converter

Rescale and Kitbash

You resize the mesh, cut it apart and combine selected forms with other models.

FBX to OBJ converter

opolyo-model.glb @ in about two minutes

What Survives STL to OBJ

OBJ stores a mesh, so that is what comes out: the same triangles the STL had, with the coordinate numbers unchanged. No quads, UVs or materials are added along the way.
GeometryColourMaterialsUnitsTopologyFile size

Geometry

The STL surface carries into OBJ with the same shape. Its triangles become OBJ face data.

STL file format

the file you have

Opolyo

the converter above

Editable OBJ container, unchanged triangle topology

INSIDE THE CONVERSION

How STL to OBJ Conversion Builds the Output

The browser reads the STL triangles and writes the same surface in OBJ syntax. The four stages below say what changes and what stays.

  1. 01

    Binary and text STL enter the same path

    The loader detects binary or text STL and turns either into the same triangle geometry.

    The exporter works from that in memory geometry. Binary and text STL therefore give the same OBJ structure.

  2. 02

    Triangle vertices become OBJ face records

    Each STL facet supplies three positions and a normal for the OBJ.

    The writer lists those positions as OBJ vertices, then connects them with face records. Modelling software gets the same triangular shell.

  3. 03

    The conversion keeps the existing topology

    Changing the container does not rebuild edge flow or infer quad faces.

    The OBJ stays a triangle mesh because those are the faces in the STL. Sculpt or retopologise it in a modelling application; the paid workspace has a quad topology option when rebuilding is the goal.

  4. 04

    Coordinate numbers remain unscaled

    STL and OBJ declare no unit, so every position is exported without a unit conversion.

    The bounding box shown before download is the checkpoint. Compare it with the size your next application expects and pick that application's import unit.

SPECIFICATIONS

STL to OBJ Specifications

Rewrites STL triangles as OBJ geometry with the coordinate values unchanged.

Input

Accepts
.stl
Size ceiling
100 MB
Read in
Your browser

Output

Writes
OBJ text
Topology
Triangles
UVs
Not created

Scale and cost

Scale
Carried through
Conversions
Unlimited
Price
Free

BEFORE YOU CONVERT

Why Opolyo, not a typical STL to OBJ converter

The difference is in what you are told about topology and UVs before you convert.
Topology
Most tools:Often relabels the triangles and says nothing about topology.
Opolyo:States that the free OBJ stays triangulated.
UV creation
Most tools:Often says nothing about UVs either.
Opolyo:States that no UVs are created; unwrapping stays in your modelling software.
Scale
Most tools:Often assigns a working unit after reading the STL coordinates.
Opolyo:Passes every coordinate through unchanged, since neither format declares a unit.
File privacy
Most tools:Often uploads the scan or print mesh to a server.
Opolyo:Reads and rewrites the STL inside your browser tab.
Retopology
Most tools:Often treats quad generation as a separate step.
Opolyo:Offers quad topology in the paid workspace; the free browser path stays triangles.
Use the browser route when a triangle OBJ is what the next tool needs. Use the paid workspace when the point of the conversion is quad topology. The converter above does it without an account.

WHAT YOU GET

Models you can spin before you download

The models below were made with Opolyo. Drag one to spin it. What you download above is the same kind of file: a real mesh you can open in Blender.

Pricing

Every credit turns into a model you keep

Billed every month. Cancel anytime.

Start

For your first prints and props

$19.99

USD

Billed monthly

  • 160 credits / month (16 generations)
  • Standard and Ultra PBR textures
  • GLB, STL & OBJ export
  • Built-in format converter
  • Failed generations refunded automatically
  • Commercial license
  • Email support
Get Opolyo

Cancel anytime.

POPULAR

Build

For people who ship models weekly

$39.99

USD

Billed monthly

  • 360 credits / month (36 generations)
  • Standard and Ultra PBR textures
  • GLB, STL & OBJ export
  • Built-in format converter
  • Failed generations refunded automatically
  • Commercial license
  • Email support
Get Opolyo

Cancel anytime.

BEST VALUE

Scale

For studios and print farms

$89.99

USD

Billed monthly

Everything in Build, plus:
  • 900 credits / month (90 generations)
  • Lowest cost per credit
  • Priority email support (24h response)
Get Opolyo

Cancel anytime.

I filled my first map in just one afternoon! That's 24 props already.

Marcus Reed

Built a Game

STL to OBJ Converter FAQ

Question not here? Ask by email.

  • Yes. The OBJ opens in Blender, Maya and ZBrush. The mesh stays triangulated.

  • No. The free browser converter creates no quads and does no retopology. The paid workspace has a quad topology option when you need that.

  • No. UV unwrapping stays a separate job in modelling software.

  • Yes. The STL triangles carry into the OBJ with the coordinate numbers unchanged.

  • Yes. The loader detects either encoding and turns it into the same triangle geometry before the OBJ is written.

  • Yes. It runs on your own computer, so it is free and uses no credits.

  • Yes. There is no sign in; the converter opens in the browser.

  • No limit on how many files. Each file can be up to 100 MB.

  • No. The file stays on your device while the browser processes it.

  • No. The tab reads the file and writes the OBJ on your machine.

  • Yes. The triangle count, object count and bounding box appear before you download.

  • No. STL stores no materials, textures or colour, so there is nothing for the OBJ to pick up.

  • No. STL declares no unit and OBJ declares none either, so the coordinates pass through without scaling.

  • They stay in the geometry. STL has no object names, so the OBJ starts as one mesh containing those separate surfaces.

  • No. The mesh is not simplified; the same STL triangles become OBJ faces. The triangle count shown before export tells you whether it is a comfortable size to edit.

  • The paid side of Opolyo generates a 3D model from one photo or a text description, and that uses credits. Converting an STL you already have into a triangle OBJ stays free.

What people make with Opolyo

5,873 makers and counting. A few of them told us what they made, and what happened next.

  • The customer's payment dashboard, a net revenue panel reading $2,605.00 with $0.00 for the comparison period
    I’m a game dev and originally started using this to turn some of my reference images into 3D assets for a project. A few of the models turned out better than I expected, so I cleaned them up and started selling them on the side too. Just crossed $2,600 in net revenue from those 3D models. Never really planned on becoming an asset seller, but I’m definitely not complaining 🙌
    N
    Nathan Brooks
  • Didn’t think a single image would get me this far. The model needed a little cleanup, but I had a solid base ready in minutes. Saved me an entire afternoon.
    D
    Dylan Reeves
  • Turned one of my kid’s drawings into a little 3D character with Opolyo. She absolutely lost it when she saw it. Probably the most fun thing I’ve made with this so far.
    K
    Kyle Brandt
  • The customer's Stripe gross volume: £231.05 for Sep 2025 to Aug 2026 against £0.00 for the twelve months before, the line flat at zero until a single month of £186.15 near the end
    Honestly didn’t expect anyone to actually pay for the 3D stuff I was making. Put a few of them up for sale just to test it and somehow made £231 from my models. Still feels a bit unreal seeing that number 😂
    O
    Owen Whitaker
  • The customer's Dodo Payments record of paid 3D requests, at a range of different amounts
    I started using Opolyo for a few custom 3D requests from clients and somehow it turned into a little side service of its own. Some people just need a quick conversion, others want more detailed work, so the order sizes are all over the place. Seeing multiple paid requests come in on the same day still feels pretty surreal. Never thought image-to-3D would become something clients actually kept coming back for.
    A
    Adam Pike
  • I use a lot of reference images when working on interior concepts, and this made it really easy to turn an object I liked into a rough 3D asset. I still adjusted a few things afterward, but it saved me from modeling the whole thing from zero.
    C
    Claire Bennett
  • Couldn’t find the exact prop I needed anywhere, so I threw the reference image into Opolyo as a last resort. The first result wasn’t perfect, but the overall shape and proportions were already there. It actually looked like the thing in my reference. After a little cleanup, it was exactly what I needed.
    J
    Jonah Reyes
  • Used it to turn a couple of product images into 3D models for our store. Took a few tries to get the best result, but still much easier than hiring someone to model everything manually.
    G
    Grant Miller
  • The customer's inbox of Stripe payment notifications: five payments, four of $14.99 and one of $125.88
    Woke up, checked my inbox and Stripe notifications just kept showing up. Most were $14.99 orders, then a $125.88 payment landed later in the day. I’m still pretty new to selling my 3D stuff, so seeing 5 sales come in on the same day was a really nice feeling. 🔥
    M
    Miles Prescott
  • I had a photo of a small figurine from years ago that I couldn’t find anywhere anymore. Tried putting it into Opolyo just to see what would happen, and the result was honestly better than I expected. It felt like bringing an old thing back to life. I still want to clean up a few details before printing it, but this is probably my favorite use so far.
    R
    Riley Fenn
  • Turned a photo into a little 3D model, printed it, and gave it to a friend for his birthday. Wasn’t expecting him to react that much 😂 He absolutely loved it. Now I’m thinking of making a few more for Christmas.
    T
    Tyler Hodge
  • The customer's Dodo Payments dashboard for their 3D commission work, totalling $181.92
    I mostly got into this because I like 3D printing and wanted to make a few custom pieces without learning modeling from scratch. Then a couple of people asked if I could make something for them too, so I started taking small requests here and there. Just hit $181.92 from custom 3D commissions. It’s not a huge number, but getting paid for something I was already doing for fun feels pretty awesome.
    W
    Wes Delaney
  • Been playing around with this for a small game project and some of the results are actually really fun. I generated a few props from reference images and one of them ended up fitting the scene perfectly. It’s staying in the game.
    E
    Evan Ross
Other converters:3D model converterOBJ to STL ConverterGLB to STL ConverterFBX to OBJ Converter

Open your STL for editing

Export the triangle OBJ above, or use paid tools for quad conversion and AI generated models.

Generate 3D Model