AI video No subscription required

Lipsync API

Lip sync as a service

Sync lip movements to audio via API. Send a video or photo URL plus audio URL, get back a lip-synced video. Supports any language. Perfect for dubbing pipelines, avatar apps, and content localization.

Lipsync API example output

How Lipsync API Works

Lipsync API uses talking-head AI models to synchronize mouth movements in a video or static photo with any audio track. The model analyzes the audio waveform, maps phonemes to mouth shapes, and renders natural lip movements frame by frame. It works with any language -- the synchronization is phoneme-based, not language-specific. You can input either a video (for re-dubbing) or a single photo (to create a talking head from a still image). Developers building dubbing pipelines, avatar applications, and content localization tools integrate lipsync as a core capability. A video platform can offer automatic dubbing in new languages. A chatbot app can make an avatar respond with natural lip movements. E-learning platforms can create talking-head instructors from a single photo. The API handles the ML complexity so you can focus on your product logic. For video input, ensure the face is clearly visible and front-facing for at least 80% of frames. For photo input, use a high-resolution frontal portrait. Audio should be clean speech without heavy background music. The API returns an async response for video processing -- use the webhook or polling endpoint to retrieve the result. Pricing is per second of output video.

How it works

1

Send a POST /v1/tools/lipsync with media and audio URLs

2

AI syncs lip movements to the audio

3

Get back the lip-synced video URL

What you'll get

Lipsync API output preview

Sync lip movements to audio via API. Send a video or photo URL plus audio URL, get back a lip-synced video. Supports any language. Perfect for dubbing pipelines, avatar apps, and content localization.

HD or 4K video output ready for social or professional use

Multiple duration options from 2s to 60s+

MP4 format compatible with all editing software

Smooth motion and natural transitions

No watermarks on any output

Consistent quality across every generation

Frequently asked questions

Do I need a subscription to use Lipsync API?
No. FairStack uses pay-per-use pricing. Add funds to your account and use any tool whenever you need it. There is no subscription, no monthly commitment, and no minimum spend.
What file formats does Lipsync API support?
Lipsync API outputs MP4. You can download results instantly after generation. All outputs are full quality with no watermarks.
How long does Lipsync API take?
Most generations complete in 15-60 seconds depending on duration and resolution. Processing time depends on the complexity of your input and the selected quality settings. You can monitor progress in real time.
Can I use Lipsync API outputs commercially?
Yes. All outputs generated on FairStack include a commercial-use license. You can use them in client work, products, marketing materials, social media, and any other commercial context.
What video and audio formats does the Lipsync API accept?
Video input: MP4, WebM, or MOV. Photo input: PNG or JPEG. Audio input: MP3, WAV, or M4A. Output is always MP4 at the same resolution as the input video or at 512x512 for photo-based talking heads. Processing time is roughly 2x the audio duration.
Can I use lipsync output in commercial products and client work?
Yes. The generated lip-synced videos are fully licensed for commercial use, including in apps, platforms, and client deliverables. Ensure you have rights to the input media (face photo/video and audio) -- FairStack does not grant rights to input content you do not own.
What are the throughput limits for production use?
The API supports concurrent requests with no hard daily limit. Each request processes asynchronously and returns results via webhook. For dubbing pipelines processing hundreds of clips, submit requests in parallel -- the system queues and distributes GPU load automatically. Pricing at $0.035-0.083 per second makes large-scale dubbing affordable.

Built for Developers & API Users

Every tool available via REST API. Batch processing, cost estimation, smart model selection, and multi-modal pipelines. Build AI into your product.

More tools for Developers & API Users:

See all Developers & API Users tools