How to Fix Foot Sliding After Retargeting in Unreal Engine: A Diagnostic Checklist
Foot sliding is a symptom, not a diagnosis. A foot can skate because the source motion already slides, the retargeting changes foot contact, or the character controller moves at a different speed from the animation. The fastest way to fix it is to find the first stage where the problem appears—before adding IK or changing a bunch of settings.
Start with the three-stage test
Use the same clip at the same playback rate on a flat floor and compare these three stages:
Source: play the original animation on its source skeleton, without retargeting.
Retarget preview: play the retargeted result on your target character in the IK Retargeter.
Gameplay: play the exported animation in a minimal Unreal test using the movement setup that will actually drive the character.
The first stage that shows the slide points to the likely cause. If the source is clean but the retarget preview slides, investigate the rig and retarget setup. If both previews are clean but the game slides, investigate movement and animation playback in gameplay.
1. Inspect the source animation before retargeting
Check the original clip at normal speed, then scrub through the contact frames. Look for a planted foot that moves across the floor, a foot that lifts too early, or a stance that does not match the target character's proportions. If the source clip already has unwanted sliding, retargeting will not magically turn it into a clean foot-locked performance.
Confirm whether the clip is intended to be in-place or to contain root displacement.
Check the floor level and character scale in the source preview.
Compare the foot-contact phase with the body's forward movement.
Test a short section first; do not diagnose from a thumbnail or a single frame.
If you are still deciding between in-place and root-motion assets, read the existing Root Motion vs In-Place Animation: A Buyer’s Checklist before choosing the movement style for your project.
2. Validate the source and target IK Rigs
When the source clip looks correct, inspect the retarget setup. Epic's IK Rig documentation describes defining matching retarget chains and setting a pelvis bone for each character; it also notes that the reference poses may need to be aligned before retargeting.
Check that the left and right leg chains include the intended upper-leg, lower-leg and foot bones on both rigs.
Verify the pelvis assignment and the root chain rather than assuming similarly named bones are equivalent.
Compare the source and target reference poses. A mismatched A-pose/T-pose or stance can change the resulting limb positions.
Preview the target at its intended scale and proportions. Avoid adjusting scale, offsets and pose simultaneously—change one variable, then re-test.
Use Epic's IK Rig Animation Retargeting documentation for the chain and retarget-pose setup.
3. Use Speed Planting when proportion differences cause the slide
For characters with noticeably different leg lengths or stances, Unreal Engine's IK Retargeter includes a Speed Planting workflow in the current documentation. It uses foot-speed curves to identify when a foot should be stationary, then pins the corresponding IK goal during those frames. This is a targeted correction, not a universal fix for every bad clip.
On the source animation, use Animation Data Modifiers to generate a translation-speed curve for each relevant foot bone.
On the target IK Rig, create foot IK goals and a suitable solver. Epic's example uses Full Body IK.
In the IK Retargeter, enable Speed Planting for the relevant leg chain and select the matching speed curve.
Adjust the Speed Threshold based on the curve's stationary range. Re-preview the motion and check for knee pops, toe drift or unwanted foot locking.
Follow Epic's Fix Foot Sliding with IK Retargeter / Speed Planting guide for the detailed setup. Property names and availability can vary by Unreal Engine version.
4. Keep root motion and in-place movement consistent
Root motion and in-place animation use different movement responsibilities. With an in-place clip, the animation supplies the pose while gameplay movement supplies the character's travel. With root motion, displacement from the animation's root bone can drive the character's movement. Mixing the two assumptions can produce skating, drifting or a mesh that moves away from its capsule.
Check whether the source and exported sequence contain root displacement.
Confirm the Animation Sequence's root-motion setting and the Animation Blueprint's Root Motion Mode agree with the clip and controller.
Do not add the clip's forward displacement on top of controller movement unless that is the intended setup.
For an in-place locomotion blend, compare the character's actual movement speed with the stride represented by the clip.
Epic's Root Motion in Unreal Engine documentation explains how root-bone displacement is extracted and applied through the Animation Blueprint.
5. If the slide appears only in gameplay
When the source and retargeter previews look clean, leave the retargeter alone for now. Check the runtime layer instead:
Movement speed versus the animation's stride and playback rate.
Blend Space inputs and the transitions between idle, walk, run and turn states.
Whether the correct exported Animation Sequence is being played.
Floor height, slopes and character capsule/mesh alignment in the test level.
If it happens only in multiplayer, reproduce it in standalone first, then compare networked movement and smoothing.
A useful rule: fix animation data when the slide is visible in the source or retarget preview; fix controller/blend/root-motion behavior when it appears only after gameplay movement is applied.
A short acceptance test before shipping the clip
Play the source clip on its original skeleton.
Preview the target retarget in the IK Retargeter.
Export the sequence and play it on the target skeleton.
Test in a flat, isolated level at slow and normal movement speeds.
Check starts, stops, turns and loop boundaries—not just the middle of a walk cycle.
Record which setting changed and keep the original asset untouched.
For another foot-contact buying checklist, see Retargeting Dance Animations: Check Foot Contact Before Buying.
Choosing a motion source for your locomotion system
If you need a different source motion, browse the real product listings and review their stated coverage and available previews before deciding. A pack is not automatically retarget-ready for every character; run the same source → retarget → gameplay test on any candidate clip.
Real AnimationShopee motion previews
These are genuine animation preview assets from AnimationShopee's media library. They show example motion; they do not guarantee that foot contact will remain correct on every target skeleton or controller.
The product artwork below identifies two relevant movement families. It is not a foot-contact test. Review the actual clip preview, then run the source → retarget → gameplay check on your target character
The listings describe motion categories and included content. They do not guarantee that a particular clip will eliminate foot sliding on your rig or controller.
FAQ
Does the IK Retargeter always fix foot sliding?
No. It transfers animation between skeletons. If the source already slides, the target proportions differ significantly, or gameplay movement does not match the clip, additional correction may be needed.
Does Speed Planting fix every walking animation?
No. It is a specific foot-pinning workflow for retargeting cases where foot-speed curves and IK goals can help. It does not repair every source-motion or controller problem.
Should I switch to root motion to stop the slide?
Not automatically. Root motion is one movement approach, not a universal fix. Choose a consistent movement design and configure the clip and Animation Blueprint to match it.
Can a purchased animation cause foot sliding?
Yes, if the source performance itself has sliding or its stride/contact does not suit the scene. But check the source preview, retarget setup and runtime movement before concluding that the animation asset is the cause.
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