LESS FRICTION. MORE MAKING.
Online 3D Tools for STL Inspection
Inspect an STL in the viewer, or calculate a target scale and download a measurement report in the size checker. Both keep your model on your device.
Open the STL Viewer
Online 3D tools that keep your file private.
ASCII and binary STL · up to 25 MB and 400,000 triangles · no uploads
STL repair & editing: choose the next step
The viewer displays geometry; the size checker measures bounds and calculates scale. They do not repair holes, split meshes, check wall thickness or certify printability. Use a mesh editor for geometry changes, then inspect the exported result.
When online 3D tools need an editor alongside them
2 documented optionsInspect the file here, make geometry changes in a mesh editor and prepare printer instructions in a slicer. The applications below handle those next steps.
Blender
ModelingFree, open-source modeling, sculpting, animation and rendering.
Organic modeling and detailed mesh control
Its broad interface takes time to learn; a render-ready mesh may still need print preparation.
Free and open source. The software license does not automatically determine the license of assets you import.
Windows · macOS · Linux · Sources checked 2026-10-16Details: formats & sources
Input: STL, OBJ, GLB, FBX
Output: STL, OBJ, GLB, FBX
Official source 1 Official source 2 Official source 3FreeRead review
Visit official website 
PrusaSlicer
3D PrintingPrepare prints, inspect layers and split models with a desktop slicer.
Layer inspection and practical print preparation
Printer compatibility and process settings matter more than simply choosing a slicer.
Free and open source.
Windows · macOS · Linux · Sources checked 2026-10-16Details: formats & sources
Input: STL, OBJ, 3MF
Output: G-code, 3MF
Official source 1 Official source 2Free
Visit official website Guides for using online 3D tools
GuideFile Formats
3D File Formats: STL vs OBJ vs GLB
Understand geometry, textures, scene data and unit limitations so you can choose an export format for printing, editing or web delivery.
Guide3D Modeling
Split a 3D Model in PrusaSlicer: Cuts and Connectors
Follow a model splitting exercise in PrusaSlicer, retain both cut objects and verify their dimensions before adding assembly joints.
Guide3D Printing
How to Convert an Image to STL
Choose an image-to-STL workflow for PNG, JPG or SVG: trace and extrude an outline, create a grayscale relief, or reconstruct an object from photos.
Your next 3D project starts with a better next step.
Discover 3D tools, model resources and practical workflow guides.