Step 1
Provide face media
Video plate or a model that accepts image + audio.
AI lip-sync for existing faces
Lock mouth motion to dialogue with models typed lipsync in config. Use it on plates you already shot or generated.
Kling LipSync · Prompt: Diner window portrait, dialogue-ready framing
What is AI lip sync?
Lip-sync models align mouth shapes on a face video (or still-driven clip) to a dialogue track. FairStack lists type lipsync only on this page.
Lip Sync models
2 models matched from config for this capability.
Kling LipSync
$0.0168/s
Kling LipSync Audio-to-Video is Kuaishou's lip synchronization model that matches video lip movements to provided audio input. The model analyzes the audio's phonemes and drives realistic lip movements, jaw motion, and subtle facial expressions in the source video to match the provided speech, producing natural-looking synchronized output. Powered by Kling AI's video generation technology and delivered via fal.ai, the model preserves the identity and visual characteristics of the person in the video while modifying only the mouth and jaw area. The synchronization handles various speaking speeds and accents, with best results on clear, well-recorded audio. Compared to lip-sync-only models like MuseTalk 1.5, Kling LipSync delivers higher synchronization accuracy and more natural mouth shapes. Against full talking head generation models, it focuses specifically on accurate lip sync for existing video rather than generating new video content. Best suited for video dubbing, lip sync for translated content, and music video creation where matching lip movements to audio produces convincing synchronized video. Available on FairStack at infrastructure cost plus a 20% platform fee. Recommended for client-facing lip sync: in our tests it kept the face sharp and closed the lips in silent pauses where the budget MuseTalk 1.5 did not.
MuseTalk 1.5
$0.0015/s
MuseTalk 1.5 is a lip synchronization model that adds natural mouth movement to existing images or video, billed per second of output. The model specializes in lip sync only, driving mouth movements from audio input without generating full body motion or head movement, keeping the processing focused. Per-second billing makes it practical for high-volume production, batch processing, and applications where hundreds or thousands of clips need lip synchronization. The model works with both static images and existing video. MuseTalk 1.5 is the lip-sync-only option: premium lip sync models like Sync Lipsync 2.0 Pro and full talking head models like Kling Avatar add facial and body animation and are priced accordingly. Best suited for lip sync at scale, adding speech to portrait photos, and high-volume video lip synchronization where cost per second matters most. Available on FairStack at infrastructure cost plus a 20% platform fee; the current per-second rate is shown on this page. Quality note: MuseTalk 1.5 is the budget option. On some clips the mouth stays slightly open through silent pauses, and on others the lower face looks softer than the rest of the frame. For client-facing work use Kling LipSync (kling-lipsync-a2v): the face stays sharp and the lips close in pauses, at a higher per-second price, for videos up to 10 seconds long.
How to use lip sync
Step 2
Add dialogue audio
Dry voice works better than mixed beds.
Step 3
Run a lipsync model
Picker is type=lipsync from config.
Step 4
Review phoneme edges
Re-run with cleaner audio if consonants smear.
Frequently asked questions
Which models appear? +
Config type lipsync — including Kling LipSync and MuseTalk 1.5 among the selectable set.
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