Blender to Mixamo Problems

So you created the dopest character ever but it will not work in Mixamo for some reason.

Try this

1. Clean Up the Geometry Mixamo needs a clean, water-tight mesh to calculate the rig properly.

• Remove Doubles (Merge by Distance): Go into Edit Mode (Tab), press A to select all vertices, press M, and select By Distance. This will weld any disconnected vertices that might be tearing your mesh.

• Recalculate Normals: While still in Edit Mode with everything selected, press Shift + N to recalculate the outside normals. Mixamo can get confused if some faces are inverted.

• Delete Loose Geometry: In Edit Mode, go to the Mesh menu > Clean Up > Delete Loose. This removes floating vertices or edges that aren't attached to faces.

2. Combine the Meshes Mixamo works best when the character is a single, unified object.

• If your character is made of multiple separate objects (like eyes, hair, clothes, and body), go to Object Mode, select all parts of the character, and press Ctrl + J to join them into one single mesh.

3. Check the Pose

• Ensure your character is in a standard T-Pose (arms straight out to the sides) or an A-Pose (arms pointing slightly down). Mixamo's symmetry algorithms rely on these poses to place the joints correctly.

• Make sure the character is facing directly forward (looking down the negative Y-axis in Blender).

4. Apply All Transforms (Crucial Step) This is the most common reason Mixamo uploads fail or look distorted.

• In Object Mode, select your character.

• Press Ctrl + A and choose All Transforms.

• This resets your character's Location to (0,0,0), Rotation to (0,0,0), and Scale to (1,1,1). Mixamo needs these values at zero/one to scale the rig appropriately.

5. Clear Existing Rigging (If Applicable) If your model already has a skeleton, vertex groups, or armature modifiers, it can interfere with Mixamo's auto-rigger.

• Delete any Armature objects in your scene.

• Go to the Modifiers Properties tab (the wrench icon) and remove any Armature modifiers.

• Go to the Object Data Properties tab (the green triangle icon) and delete all existing Vertex Groups.

6. Exporting the FBX for Mixamo Once the mesh is repaired, you need to export it with specific settings:

• Go to File > Export > FBX (.fbx).

• Under the Include settings, check Selected Objects (ensure your character is selected).

• Under Transform, leave the scale at 1.00. Set Forward to -Z Forward and Up to Y Up (Mixamo uses standard Y-Up orientation).

• Under Geometry, set Smoothing to Face.

• Uncheck Bake Animation and ensure you are not exporting any armatures.