To reduce the polygons of a model you generated with Meshy or Tripo, download it as GLB and run it through a simplifier that keeps the texture: drop the file into Decimify, drag the slider to the face count you want, and export a new GLB with the same textures and UVs. Nothing is regenerated, so the model you picked is the model you keep — just lighter.
Why AI-generated models come out so heavy
The face count is decided at generation time. Tripo’s v3.1 model generates up to 1,500,000 faces (2,000,000 with detailed geometry) and picks the number adaptively when you leave the limit empty (Tripo docs). Meshy’s Remesh aims at a target polycount from 100 to 300,000, 30,000 by default, and its own docs warn that the real count may deviate (Meshy docs). Both hand you a textured model. That looks fine in the generator’s viewer and turns into a slow SketchUp scene, a heavy web viewer or a game asset over budget.
Reduce in the generator, or after you download?
| When | Face range | Same model you picked? | |
|---|---|---|---|
| Tripo smart low-poly | At generation, +10 credits | 500–20,000 faces; “for simple inputs” | No — a new generation |
| Meshy Remesh | After generation, a credit-metered task | 100–300,000 target | Rebuilds the mesh; the docs do not say what happens to the texture |
| Decimify | After download, free | Any level, from the original down | Yes — fewer faces, GLB textures and UVs kept |
The generator’s own option is the right call when you know the budget before you generate. When you already have a model you like and only need it lighter — or three versions of it at different weights — reducing the file you have is faster than paying for another run and hoping it comes out the same.
Reduce a Meshy or Tripo model in four steps
- In Meshy or Tripo, download the model as GLB. GLB carries the textures; an STL comes out geometry-only.
- Open Decimify online, sign in with your free 3dshouse account and click Choose file.
- When the progress bar finishes, drag the reduction slider and watch Faces and Ratio. Every level is ready before you touch the slider, so it moves instantly in both directions, and level 0 is the original exactly.
- Under Export, click GLB. Working in SketchUp? The Decimify plugin opens the same GLB and puts the reduced model straight into your scene with Load to Origin.
Four things to check before you export
- The slider barely moves? The texture is pinned per face, and Maintain UV (on by default) refuses to tear it. Turn it off in Settings to reduce freely, at the cost of small seams between faces.
- Compressed GLB opens, the export is uncompressed. Draco, meshopt and KTX2 files load fine — Tripo can write meshopt-compressed geometry — but the result is a plain GLB, so it can be larger on disk even with far fewer faces. Re-compress it afterwards if download size matters.
- Vertex colours are not carried. A model coloured only by vertex colours loses them; a textured one does not.
- Units: GLB stores no length unit, so the size chip resets to metres on load — set the dropdown beside it before you judge the dimensions.
Not sure the polygons are the problem in a SketchUp file at all? The SketchUp polygon reducers compared starts with the causes that are not polygon count.
FAQ
How do I reduce the polygons of a Meshy model?
Download it as GLB, open it in Decimify online, drag the reduction slider to the face count you want and export a new GLB. The textures and UVs come along, and nothing is regenerated, so it stays the model you chose.
Does reducing polygons keep the texture of an AI-generated model?
In a GLB, yes: Decimify keeps materials and UVs while Maintain UV is on. An STL carries no texture at all, so always download the GLB.
Is there a free 3D model simplifier online?
Decimify runs in the browser for free with a 3dshouse account and a daily export allowance. The model is reduced on your own machine and never uploaded.
Free: limited to 3 exports a day
Pro: unlimited, guaranteed to work, priority support
