afk.ai/Auto-rig/Frogs and toads
Auto-rig a frog or toad with AI
A frog sits folded up, its back legs tucked in a Z under the body and longer than the whole frog once they kick out. A four-legged rig bends them in all the wrong places. afk.ai's frog skeleton has 31 joints, with back legs in four parts that fold flat and stretch all the way out, a throat that puffs out and a tongue that snaps. Upload your frog and it hops in minutes.
Before is the sample model as it's uploaded: a mesh with no bones. After is the same frog on afk.ai's skeleton, playing its animations.
How it works
- 1
Upload
Drop in your frog as a GLB, a self-contained glTF or an FBX. Sign in with Google; it's free.
- 2
The AI finds its body
An AI reads the mesh and works out where everything is. On a good graphics card it runs right in your browser; otherwise the cloud rigger does it.
- 3
Skeleton and skin
afk.ai fits its frog skeleton to what the AI found and weights the skin, so the mesh bends at the joints.
- 4
Animate and export
Preview every animation on your model, then download one GLB with the skeleton, skin weights and all of the animations.
What the frog rig includes
Frogs and toads: a short body, short front legs, long folding back legs, a jaw, a throat and a tongue.
Skeleton: 31 joints
- Hips and a two-bone spine
- Head with a jaw, a throat and a two-bone tongue
- Two front legs from the upper arm to the hand
- Two back legs in four parts: thigh, shin, ankle and foot
13 animations
Hop, Big Jump, Land, Idle, Croak, Puff Up, Tongue Snap, Catch Fly, Swim, Climb, Splat, Hit, Death.
Download the rigged frog (.glb, 0.8 MB)The sample above with its skeleton and all 13 animations. CC0: use it for anything.
Models that rig best
- A frog sitting with its back legs folded at its sides fits best: that's the pose the skeleton rests in.
- A frog character that stands on two legs, like a frog knight, rigs better as Humanoid.
- A frog on a lily pad or a rock: choose Select a part on afk.ai/rig and draw around the frog, so only the frog moves.
Use your rigged frog in Unity, Unreal, Godot or Blender
Unity 6
- Open Window > Package Manager, click +, choose Add package by name and enter com.unity.cloud.gltfast (glTFast).
- Drag the .glb into Assets. It becomes a prefab with the mesh, skeleton and one Animation Clip per animation.
- Create an Animator Controller, drag the clips into it and assign it to the Animator on the prefab.
- Prefer FBX? Export one from Blender, then in Unity set Rig > Animation Type to Generic (creatures aren't Humanoid avatars) and click Apply.
Unreal Engine 5
- Drag the .glb into the Content Browser (or +Add > Import). Unreal 5.1 and later import glTF natively.
- Click Import in the options dialog. You get a Skeletal Mesh, its Skeleton, a Physics Asset and one Animation Sequence per animation.
- Creatures keep their own skeleton, so there's nothing to retarget to the mannequin.
Godot 4
- Copy the .glb into your project folder. Godot imports it as a scene with a Skeleton3D and an AnimationPlayer holding every animation.
- For cycles like walks and idles, double-click the .glb, select the animation, set Loop Mode to Linear and click Reimport.
- Instance the scene and play one: $AnimationPlayer.play("Hop").
Blender
- File > Import > glTF 2.0 (.glb/.gltf), and pick the file.
- The mesh comes in on its armature, with the first animation active: scrub the timeline to play it.
- The other animations are on NLA tracks named after them. Click a track's star (Solo) to play it.
Questions
›Do the tongue and throat move?
Yes. The frog skeleton has a throat bone and a two-bone tongue: Croak swells the throat, and Tongue_Snap and Catch_Fly shoot the tongue out.
›Which animations are included?
Hop, Big_Jump, Land, Idle, Croak, Puff_Up, Tongue_Snap, Catch_Fly, Swim, Climb, Splat, Hit and Death. All of them are in the download.
›Is it free for commercial use?
Yes. Your model stays yours and the animations are CC0.
›Is afk.ai free?
It's free to try: rigging your model and previewing its animations cost nothing. You sign in with Google, and the site is supported by ads.
›What do I need to run it?
A computer with Chrome or Edge. With a decent graphics card the AI runs in your browser (the first rig downloads the 1.1 GB AI model once). On phones and weaker computers, afk.ai offers its cloud rigger instead.