Lip Sync works best when the input clearly shows one visible face and the audio is clean and easy to follow.
If your lip sync result fails, cuts off, or looks unnatural, the issue is usually related to the face visibility, audio clarity, or source video format.
Best practices
For best results:
use videos where there is at least some mouth movement, especially in the first 2 seconds
use a clear front-facing face
keep the subject large enough in frame
avoid blocked mouths
avoid rapid movement
use clear speech audio
avoid overlapping voices
test shorter clips first
Common problems and fixes
The lips do not match the audio Try:
using clearer speech audio
using a source video where the face is more visible
avoiding heavy side angles
removing background noise from the audio
The mouth movement looks unnatural Try:
using a better-lit source video
using slower and clearer speech
avoiding input videos where the face is too small or partly hidden
The project fails Try:
re-exporting the source video as MP4
trying a shorter clip
re-uploading the input files
checking that the face is clearly visible throughout the clip
The output is cut off or incomplete Try:
shortening the input
confirming the full audio was uploaded properly
retrying with a shorter sample clip before rendering the full version
What to include when contacting support
Please include:
your project ID
the tool page URL
whether the issue was failure or bad quality
source video length
source audio type
what you expected
Related links: