Using Mixamo with an AI-generated character

What Mixamo is

Mixamo is Adobe's free auto-rigging and animation service. It's available to anyone with an Adobe ID, and Adobe's FAQ says you can use its characters and animations royalty-free in personal, commercial and non-profit projects. Its auto-rigger and animation library are for bipedal humanoids only.

For an AI-generated humanoid, it's usually the fastest route to a moving character.

What Mixamo needs

Adobe's FAQ lists the conditions for a successful auto-rig. In short:

• A bipedal humanoid with distinguishable head, body, arms and legs.
• A neutral, default pose (T- or A-pose).
• No extra objects, cameras or helpers in the file.
• No gaps between body parts.
• A clean, error-free mesh.
• Centred at the world origin.

And it can fail on: heavily exaggerated proportions, large extra appendages (wings, tails, big hair or clothing), and asymmetric or pre-posed characters.

AI-generated characters often break one or two of these. Here's how to fix that.

Step 1: Generate with Mixamo in mind

• Use an input in a neutral A- or T-pose, front-facing, arms away from the body, legs apart, hands open or relaxed, no props.
• Avoid huge capes, wings and very long hair for the first attempt.
• In Vi3W, check the generated image before the 3D step: if the arms touch the body there, they'll be fused in the mesh.

A-pose vs T-pose explains which to choose.

Step 2: Clean the mesh in Blender

1. Import the GLB or FBX.
2. Delete everything that isn't the character (empties, ground planes).
3. Join body parts into one mesh (Ctrl+J) unless clothes need to stay separate.
4. Merge by Distance in Edit Mode.
5. Fix fusions: separate fingers or arms from the torso if they're merged.
6. Scale to a real height and centre on the origin, feet on the ground.
7. Ctrl+A › All Transforms.
8. Export FBX (or OBJ). If textures are needed, embed them in the FBX or zip them with an OBJ.

Step 3: Upload and place markers

1. Upload the file in Mixamo.
2. Mixamo asks you to place markers: chin, wrists, elbows, knees and groin.
3. Choose a skeleton level of detail (fewer or more finger bones).
4. Wait for the auto-rig, then check the preview animation.

Step 4: Fix common failures

• Rig fails or limbs swap: check the character faces forward and is centred; re-place markers.
• Arms deform into the body: they were too close in the mesh; separate them more.
• Fingers fused: use fewer finger bones, or separate fingers in Blender.
• Hair or cape stretches: separate these as their own mesh and rig them in Blender afterwards, or simplify.
• Strange proportions: very large heads (chibi) can confuse markers; place them carefully.

Step 5: Animations and download

Pick animations from the library, adjust parameters, and download FBX for Unity (or for Unreal). Download "with skin" for the first one and "without skin" for extra animations to keep files small.

• Unity: import the FBX, set the Rig tab to Humanoid to use Mecanim retargeting.
• Unreal: import as a skeletal mesh; retarget animations as needed.
• Godot: convert to GLB in Blender, or import FBX on Godot 4.3+.

Licensing reminder

Adobe's community FAQ notes the main limit is redistributing raw Mixamo files (for example, selling them as an asset pack). Using rigged characters and animations inside your game is fine under their terms.

Need a humanoid to rig? Generate one in Vi3W in a clean A-pose and send it straight to Mixamo.