The best lip sync AI depends on the input. To re-sync an existing video, Sync is the most fully documented cloud tool and MuseTalk or LatentSync the open-source route; to make a still image talk, use Hedra Character-3 or InfiniteTalk. A 30-second clip runs from about $0.69 to $3.99 at October 2026 list rates. Wav2Lip is non-commercial only. This is a documentation-based comparison, not a scored test.
The best lip sync AI depends on what you are syncing: to put new audio on an existing video, Sync is the most fully documented cloud tool and MuseTalk or LatentSync the open-source route, and to make a still image talk, Hedra Character-3 in the cloud or InfiniteTalk on your own GPU. At October 2026 list rates a 30-second clip costs between about $0.69 and $3.99 in the cloud, and nothing per clip on open models if you have the hardware.
Checked October 2026 against Sync's billing docs, model docs and pricing, Magic Hour's Lip Sync page and pricing, Kling's Lip Sync page and guide, Hedra's Character-3 page, and the LatentSync, MuseTalk, Wav2Lip, InfiniteTalk and SadTalker repositories.
Read this as a documentation-based comparison. We have not run every tool on the same clip and scored the mouths, so nothing below claims one model looks better than another. What the page does is line up what each vendor and repository commits to in writing: inputs, length limits, resolution, price per second, watermark and license. Those decide which tools you can use at all, before quality comes into it. For the wider video stack, see our AI influencer video generators ranking.
What a lip sync AI tool does, and the three jobs hiding in the name
"Lip sync" gets used for three different jobs, and most bad results come from using a tool built for one on another:
- Re-sync a video. You have footage of a face and new audio: a fixed line, a dub, a song. The tool repaints the mouth region. Sync, Magic Hour, Kling Lip Sync, LatentSync, MuseTalk and Wav2Lip do this.
- Animate a still. You have one image and audio. The tool generates the whole performance. Hedra Character-3, InfiniteTalk and SadTalker do this, as do the avatar tools in our AI talking avatar guide.
- Generate the speech with the video. Models with native audio create the clip and the dialogue together, so there is nothing to sync afterwards.
Best lip sync AI: the verdict by job
- Fix or replace a line in existing footage: Sync lipsync-2. It is the default its own docs recommend for most videos, at $0.05 a second.
- Hard footage (profile angles, partly covered faces, 4K): Sync sync-3, which is documented for exactly those cases at $0.133 a second.
- Long files in one pass: Magic Hour, whose full tool lists a maximum of 83 minutes at 24 fps.
- A clip you made in Kling: Kling Lip Sync, without leaving the app.
- One image that needs to speak or sing: Hedra Character-3, up to 10 minutes.
- Free, local and allowed for paid work: MuseTalk.
- You sync a few clips a week
- You have no GPU with 8 GB or more of VRAM
- You need 4K output or files longer than a minute
- Your time costs more than a few dollars a clip
- You sync at volume and per-second fees add up
- You already run ComfyUI or Python locally
- Footage cannot leave your machine
- You have read the license and it covers your use
Lip sync AI tools compared
| Tool | Type | Input | Documented limits | Price | Watermark or license |
|---|---|---|---|---|---|
| Sync, lipsync-2 | Cloud | Video plus audio | 512 by 512 face model; clips up to 1 minute on Hobbyist, 5 on Creator, 30 on Scale | $0.05 a second, plus a plan from $5 a month | Watermark until the Creator plan |
| Sync, sync-3 | Cloud | Video plus audio | 4K native output; documented for extreme angles and partial faces | $0.133 a second | Same plans as above |
| Magic Hour Lip Sync | Cloud | MP4 or MOV up to 4K, plus audio | 83 minutes at 24 fps in the full tool; 10 seconds in the free tool | From 24 credits a second; API from $0.023 a second | Free results watermarked and non-commercial |
| Kling Lip Sync | Cloud | A clip generated in Kling, plus audio or text to speech | Human characters with a complete face; no animals | Paid feature; cost shown before you generate | Follows your Kling plan |
| Hedra Character-3 | Cloud | A still image plus audio | Up to 10 minutes; 540p, 720p or 1080p | 2.5, 5 or 6.25 cents a second through the API | Free outputs watermarked and non-commercial |
| LatentSync 1.6 | Open source | Video plus audio | Trained at 512 by 512; at least 18 GB VRAM (8 GB for 1.5) | Free on your own GPU | Code Apache-2.0; checkpoints tagged OpenRAIL++ |
| MuseTalk 1.5 | Open source | Video or image, plus audio | 256 by 256 face region; 30 fps or more on a Tesla V100; tested on 4 GB | Free on your own GPU | MIT; commercial use allowed |
| Wav2Lip | Open source | Video plus audio | Published in 2020; trained on low-resolution faces | Free on your own GPU | Personal, research and non-commercial use only |
| InfiniteTalk | Open source | Video or image, plus audio | 480p or 720p; unlimited length; moves head and body as well as lips | Free on your own GPU | Apache 2.0 |
| SadTalker | Open source | A still image plus audio | 256 and 512 face models; last changelog entry is from 2023 | Free on your own GPU | Apache 2.0 |
All rows checked October 2026 on the pages linked at the top. Sync bills per output frame using 25 fps as the reference for its per-second prices. Magic Hour and Hedra prices are the "from" and API rates on their pages; subscription credits may convert differently.
What a 30-second talking clip costs
Thirty seconds is a useful unit: one talking Reel, or one verse of a song. Multiplying each published per-second rate by 30 gives the figures below. They exclude subscription fees and retakes.
Source: Sync billing docs, Magic Hour Lip Sync and pricing pages, Hedra Character-3 page; checked October 2026. Per-second list rate x 30; plan fees and retakes excluded.
The Magic Hour credit figure uses its stated 24 credits a second and its listed pack of 4,000 credits for $10. Sync's usage is charged on top of a plan: Hobbyist at $5 a month keeps a watermark and caps clips at one minute, and Creator at $19 removes the watermark and allows five minutes. Kling's guide gives 5 credits for a 5-second lip sync and says the current cost is shown before you generate, so budget roughly 30 credits for the same half minute, plus the cost of generating the clips themselves.
The cloud tools, one by one
Sync: the specialist, with a model for each difficulty
Sync comes from the people behind Wav2Lip; the Wav2Lip repository points commercial users to it. Its model docs describe four lip sync models. lipsync-2 is the default for most videos, lipsync-2-pro adds diffusion-based super resolution and runs 1.5 to 2 times slower, and sync-3 outputs 4K natively and is documented to handle extreme angles, partial faces and obstructions. lipsync-1.9 is the fast legacy model with generic mouth shapes.
Limits it states itself: lipsync-2 and 2-pro need natural speaking motion in the input video and can struggle on extreme profile views; no model supports animals or non-humanoid characters; several speakers in frame is a common cause of poor results, with active speaker detection available from the Creator plan.
Magic Hour: long files and an open front door
Magic Hour's Lip Sync page accepts MP4 and MOV files up to 4K with your own recording, generated speech or a cloned voice, and lists a maximum of 83 minutes at 24 fps in the full tool. Pricing starts at 24 credits a second, and paid subscribers and credit-pack buyers hold full commercial rights to the output. Its free tool is covered in our free lip sync AI comparison.
Kling Lip Sync: only for Kling clips
Kling's Lip Sync adds speech or singing to a clip you generated in Kling: choose the clip, upload audio or use Text to Speech, and it reworks the mouth. It supports realistic, 3D and 2D human characters with a complete, visible face, does not support animals, and is described as a paid feature. It does not take a still image; Kling sends those to its separate avatar feature.
If you are starting a new Kling clip anyway, compare it with Native Audio in VIDEO 3.0, which generates the dialogue and the performance together in Chinese, English, Japanese, Korean or Spanish. Our Kling image-to-video tutorial covers that setting.
Hedra Character-3: when all you have is an image
Hedra's Character-3 takes a start frame and an audio file and generates up to 10 minutes of performance at 540p, 720p or 1080p, in ratios including 9:16. It is not a re-sync tool: it will not fix the mouth in footage you already shot. Free outputs are watermarked and non-commercial; paid plans carry commercial rights.
The open-source tools, and the license that trips people up
- LatentSync (ByteDance). A latent diffusion lip sync model. Version 1.5 added a temporal layer for consistency and runs in 8 GB of VRAM; version 1.6 was trained at 512 by 512 to reduce blur and needs 18 GB. The code is Apache-2.0 and the checkpoints are tagged OpenRAIL++ on Hugging Face, so read both before client work.
- MuseTalk. Not a diffusion model: it inpaints a 256 by 256 face region in one step, which is why it reaches 30 fps or more on a Tesla V100. The repository lists its own limits plainly: resolution below the theoretical bound, some loss of details such as moustache and lip colour, and some jitter.
- Wav2Lip. The 2020 model that started the category. It still syncs any video to any audio, at low face resolution, under the non-commercial terms above.
- InfiniteTalk. Dubs an existing video or animates an image from audio, moving the head, body and expression as well as the lips, with no fixed length cap. Apache 2.0. Its repository notes colour shifts past about a minute when starting from a single image.
- SadTalker. One portrait plus audio gives a talking head. Apache 2.0 since its non-commercial restriction was removed; its changelog stops in 2023.
Running these means a GPU and some setup. Our best ComfyUI models guide covers the local side, and the cloud GPU comparison covers renting one by the hour.
AI lip sync for music videos
Singing is harder than speech: held vowels, wide mouth shapes and a backing track that confuses the model. Three vendors document it. Sync's docs answer "can it do singing" with a plain yes, recommend sync-3 for best quality and lipsync-2 as the default, and tell you to isolate and upload the vocal track. Kling accepts an uploaded singing file. Magic Hour lists music lip-sync edits among its use cases.
- 1Isolate the vocal
Export the vocal stem, or separate it from the mix. Sync the model to the voice alone.
- 2Cut the song into sections
Verse, chorus, bridge. Each section must fit your plan's length cap: 20 seconds free, 1 minute on Sync Hobbyist.
- 3Shoot or generate singing footage
The face should already look like it is singing: mouth moving, front or three-quarter angle, nothing covering the lips.
- 4Sync each section
Same model and settings for every section so the mouth style matches across cuts.
- 5Lay the full mix back
In the edit, replace the vocal stem with the mastered track and line it up on the first consonant.
- 6Cut on the beat
Change shot every few seconds. Short cuts hide the frames where the mouth drifts.
Best lip sync AI free: the short answer
Magic Hour's free tool gives three lip syncs a day of up to 10 seconds with no account, and a free Sync account gives three generations a month of up to 20 seconds; both are watermarked. Local models are the only unlimited free route. The full length, watermark and license matrix is in free lip sync AI: tools with no watermark and real limits.
Why lip sync fails, and what to check first
The cause the vendors name most often is the source footage, not the model. A re-sync tool edits the mouth it is given. If the face in the source is still, turned away or half hidden, there is little for it to work with.
- The face in the source video is already moving as if speaking
- Front or three-quarter angle, with the mouth unobstructed for the whole clip
- One speaker in frame, or a plan with active speaker detection
- Clean audio: voice only, no music bed, no long silences
- Clip length inside the plan cap, trimmed to match the audio
- Human or human-like character; no animals
- Footage and voice are yours, or you have written permission for both
- License checked if a brand is paying, especially for open models
That seventh line matters more here than anywhere else in AI video. Lip sync on a real person's footage puts words in their mouth. Only sync footage and voices you own or have consent to use; our AI likeness rights guide covers where the lines are.
When to skip lip sync entirely
- You have not made the video yet. Generate it with speech built in. Kling VIDEO 3.0 and Google's video models produce dialogue with the clip, which avoids a second pass. See how to make AI influencer videos.
- The format is a presenter talking for a minute. Use an avatar tool, which holds the framing and bills by the minute.
- You are translating finished videos. Dubbing tools bundle translation with lip sync: HeyGen lists video translation with lip-sync at 6 or 10 credits a minute, and Synthesia lists dubbing with lip-sync at 80 credits a minute.
- You can act the line yourself. Runway's Act-Two transfers a performance you record, lips and expression included, onto a character at 5 credits a second, according to Runway's help center.
Choosing between these per format, and wiring voice, face and video into one weekly routine, is what the AI Influencers program teaches.
Lip sync AI: FAQ
What is the best lip sync AI?
It depends on the job. To re-sync an existing video to new audio in the cloud, Sync publishes the fullest specification: per-second prices for each model, clips of up to 30 minutes on its top plan and 4K output from sync-3. To make a still image talk, Hedra Character-3 takes an image and audio for up to 10 minutes. These picks rest on documentation checked October 2026, not on a scored test.
What is the best open source lip sync AI?
For commercial work, MuseTalk is the safest documented choice: its code is MIT licensed, its repository says the model can be used commercially, and it was tested on a 4 GB laptop GPU. LatentSync 1.6 was trained at 512 by 512 to reduce blur and needs at least 18 GB of VRAM. Wav2Lip still works for tests but is limited to non-commercial use.
Can I use Wav2Lip commercially?
No. The Wav2Lip repository says it can only be used for personal, research and non-commercial purposes, and that because the models were trained on the LRS2 dataset, any form of commercial use is strictly prohibited. Its authors point commercial users to their hosted product, Sync. For paid work on your own GPU, use MuseTalk or read the LatentSync licenses instead.
Which lip sync AI works for music videos?
Sync, Kling and Magic Hour all document singing. Sync's docs recommend sync-3 for the best quality on songs, lipsync-2 as the default, and uploading the isolated vocal track rather than the full mix. Kling Lip Sync accepts an uploaded singing file on Kling-generated clips, and Magic Hour lists music lip-sync edits among its uses. Cut the song into sections that fit your plan's length cap.
How much does AI lip sync cost?
At October 2026 list rates, a 30-second clip costs about $1.50 on Sync's lipsync-2 and about $3.99 on sync-3, on top of a plan from $5 a month. Magic Hour starts at 24 credits a second, about $1.80 for 30 seconds at its credit-pack rate. Hedra Character-3 costs $0.75 to $1.88 through its API depending on resolution. Open models cost nothing per clip on your own GPU.
Does lip sync AI work on AI-generated video?
Yes, with one condition that vendors spell out: the character has to look like it is talking in the source clip. Sync's docs say lipsync-2 needs natural speaking motion in the input and suggest adding "person is speaking naturally" to the prompt when you generate the video. Kling's own Lip Sync only works on clips made in Kling, with a complete, visible human face.
Is there a free lip sync AI?
Yes, in small amounts. Magic Hour's free tool allows three lip syncs a day of up to 10 seconds with no account, watermarked. A free Sync account gets three generations a month of up to 20 seconds, also watermarked. Open models such as MuseTalk and LatentSync are free without limits if you have the GPU. Kling describes its Lip Sync as a paid feature. Checked October 2026.
The mouth is the last step. Build the persona that speaks.
Lip sync only works on a face and a voice that already hold together. AI Influencers, included in All Access, covers the consistent character, the persona voice and the video workflow around them, with the other three programs, live coaching and the private community in one subscription.
Keep up with the models
Lip sync models and prices change month to month. The free Telegram channel posts the changes that matter for persona video.