Which axis orientation difference commonly causes issues when exporting FBX from Blender to Unity?

• A. Blender uses X up; Unity uses Y up.
• B. Blender uses Z up; Unity uses Y up.
• C. Both use Y up.
• D. Unity uses Z up; Blender uses X up.

Answer: (B)

When moving assets between Blender and Unity, the way axes are oriented matters because each program treats up and forward directions differently. Blender uses Z as the up axis, while Unity uses Y as the up axis. That mismatch can make a model look rotated or standing on its side, and can even affect animations if bones or pivots are imported with the wrong orientation.

To avoid this, export the FBX with axis mapping that converts Blender’s coordinates to Unity’s. A common and effective setup is to export with Forward as -Z and Up as Y, and ensure transforms are applied so rotation and scale are baked into the mesh. This aligns Unity’s expectations (Z forward, Y up) with the data from Blender, preventing the usual orientation issues.

The other options don’t reflect Blender’s default up axis or Unity’s up axis, so they don’t capture the actual mismatch you’re correcting for.