# What is IK/FK switching in a character rig?

> IK/FK switching lets one limb change between inverse kinematics and forward kinematics during a shot. You use IK while a hand or foot is in contact with something and FK while it moves freely. Snapping (or matching) sets the new mode's controls to the current pose at the switch frame, so the limb does not jump.

Updated November 2026. Source: https://www.exodeui.com/questions/what-is-ik-fk-switching/

## Key takeaways

- Switching changes a limb between IK and FK mid-animation
- Use it when contact starts or ends: grabbing, letting go, landing
- Snapping matches the controls so the pose does not pop
- Some tools blend with an IK strength or mix value instead
- Plan switch frames in your blocking pass

## Frequently asked questions

### Why does my arm jump when I switch from IK to FK?

The FK controls were not matched to the IK pose. Snap or match them at the switch frame.

### Do all 2D tools support IK/FK switching?

Not all in the same way. Some have a switch, others blend IK strength or mix. Check your tool's docs.

### Is IK/FK switching needed for simple animations?

Often not. Use it for shots with contact changes, such as grabbing or landing.

### What is an IK mix or strength?

A value from 0 to 1 that blends between the FK pose and the IK solution.

## Related

- [What is FK and IK in animation?](https://www.exodeui.com/questions/what-is-fk-and-ik-in-animation)
- [FK vs IK: when to use each](https://www.exodeui.com/questions/fk-vs-ik-when-to-use-each)
- [How to rig a 2D character with IK](https://www.exodeui.com/questions/how-to-rig-a-2d-character-with-ik)
- [Best 2D rigging software with IK and FK](https://www.exodeui.com/best-2d-rigging-software-ik-fk)