Compare two 3D model files.
See every geometric change.
A true volumetric diff for 3D-printable models - what's added and what's removed, side by side. Reads .stl, .obj and .3mf. Runs entirely in your browser. Your files never leave your device.
No signup
No account, no email, no login to compare two models. Drop them in and you're comparing.
Core comparison is free
Compare two models locally without an account. Sign in only when you need saved or multi-model workflows.
Security first
The comparison runs entirely in your browser via Web Workers - your models and their geometry are never uploaded. No tracking cookies, no third-party analytics; just anonymous, aggregate usage stats (file sizes, timings - never your files).
Add your Original (A) and Modified (B), as .stl, .obj or .3mf - the two sides need not be the same format. Files stay in your browser - nothing is uploaded.
B is automatically aligned against A to sub-voxel precision, then the volumetric diff is computed locally.
Added geometry highlighted in one colour, removed in another, with three palettes to pick from. Toggle layers, switch modes, and read live volume stats.
Need details about display modes, alignment or sensitivity? See the Comparison Tool FAQ.