FBX Scale Problems in Unity
Models arrive 100 times too big or too small
Also known as: Unity model too big · Unity model too small · Blender to Unity scale · Unity scale factor 0.01 · Convert units Unity · Unity FBX scale
Quick answer
A model arrives 100 times too big or too small in Unity because the file's units differ from Unity's, where one unit is one meter. Fix it in the model's import settings by checking Convert Units or changing the Scale Factor, and fix it at the source by exporting with consistent units. From Blender, set Apply Scalings to FBX Units Scale in the FBX exporter and keep the scene unit scale at 1.
How to fix it
Make a one-meter cube in your 3D tool, export it and check that it matches Unity's default cube; once it does, your units are right. Avoid fixing scale by changing the object's scale in the scene, because that spreads wrong values through colliders, particles and physics. Set the import preset once and reuse it across the project so every artist exports in the same way.
Tools that use FBX Scale Problems in Unity
See also
FBX
The standard 3D exchange format for games
Pivot Point
The origin a mesh transforms around
Game-Ready Asset
Asset prepared to run in a real-time engine
Static Mesh
Non-deforming geometry asset in Unreal Engine
Scale Looks Wrong in a 3D Environment
Props and buildings feel too big or too small
Human Scale and Reference Units
Real-world sizes used to keep assets consistent