ai video dubbing · lip-sync layer

AI video dubbing — re-sync any talking video to new audio.

Keep the original footage, swap the language. The Video Lip Sync API re-aligns the speaker's mouth to your new-language track, so a dubbed clip looks like it was filmed in that language — not awkwardly out of sync.

Video + audio → re-synced MP4 Lip-sync that looks real n8n-ready webhooks

Real output — a presenter re-synced to a new voice-over via the Video Lip Sync API.

// how AI dubbing works here

How AI dubbing works here

This is the lip-sync layer that makes dubbing look real — not a one-click translator. You bring the footage and the new-language audio; the API re-aligns the mouth to match. Three honest steps.

1

You have a talking-head video

Start with any clip of a person speaking to camera — a presenter, a course host, a spokesperson. Host it at a public URL or upload it so the API can read it.

2

You supply the new-language audio

Bring the translated track yourself: a voice-over recording, a dub, or a text-to-speech render in the target language. The speech and the voice are yours — the API does not translate or generate them.

3

The API re-syncs the lips

Submit both to video-lip-sync. The model re-aligns the speaker's mouth to your audio and returns a natural-looking dubbed MP4 — original footage, new language.

i

Honest scope: we do the mouth re-sync — the lip-sync layer. Bring your translated / voice-over audio (or generate it with a TTS step), and the API re-syncs the lips. It does not auto-translate the speech or generate the voice for you.

# re-sync a talking-head video to new-language audio
POST /api/ai/jobs
{
  "model_id": "video-lip-sync",
  "video_urls": ["presenter.mp4"],
  "audio_urls": ["voiceover-es.mp3"]
}
# → { "job_id": "a1b2", "status": "queued" }

GET /api/ai/jobs/a1b2
# → { "status": "done",
# "video_url": "…/dubbed.mp4" }
// two ways to dub

Two ways to dub

Pick by what you're starting from. Re-sync real footage you already have, or lip-sync a talking-character clip natively across languages. Same API key for both — switch the model_id to change the model.

re-sync existing footage

Video Lip Sync

Take a talking-head video you already have and a new-language audio track. video-lip-sync re-aligns the mouth to that audio, so the dubbed clip reads as natural. Best for localizing real presenters and spokesperson footage.

What it is: mouth re-sync of existing footage to audio you provide. Keep the original video — only the language changes.
multilingual lip-sync

HappyHorse 1.1

Native multilingual lip-sync for talking-character clips. Drive a character to speak in your target language with mouth movement that matches the audio — a strong fit for animated hosts and character-led explainers.

What it is: native lip-sync for talking characters across languages. You still bring the new-language audio.
// use cases

Localize talking-head video at scale

Because it's an API, dubbing becomes a step in a pipeline — a backend job or an n8n flow that re-syncs each clip to the audio you supply, no editor in the loop.

Localize a presenter video

Take a presenter clip and a translated voice-over, send both to video-lip-sync, and get a version where the mouth matches the new language — the same footage, localized.

Dub a course or explainer

Loop over your lesson clips with one new-language audio track each, submit a lip-sync job per clip, and collect the re-synced videos by webhook — a course localized into another language in one run.

Update a spokesperson clip

Reuse an existing spokesperson video with fresh audio — a new script or a new language — and re-sync the lips to it, instead of re-filming the talent.

AI dubbing translator workflow

An AI dubbing translator replaces spoken audio in a video with speech in another language. A solid workflow separates transcription, translation, voice generation, timing, mixing, and export. Keeping those steps separate makes bad translations and sync errors easier to fix.

Automatic video dubbing works best when the source has clear speech, little background noise, and one speaker at a time. Keep the original transcript so you can review names, technical terms, and sentences whose translated length no longer fits the scene.

If you need translated audio as part of a larger workflow, see how AI video dubbing handles speech, timing, and language changes.

Dubbing API and Python integration

A dubbing API usually accepts a video or audio file, a source language, a target language, and voice settings. Processing is asynchronous on many services: your Python script submits a job, stores its job ID, checks the status, and downloads the result when it is ready.

For a dubbing API Python integration, also handle upload limits, timeouts, failed jobs, webhook verification, and retries. Do not retry every error blindly. An invalid language code will not become valid on the next attempt.

A typical request may send source_language, target_language, voice_id, and a callback URL. Exact field names differ by provider. Compare the moving parts of an AI video API before wiring one into production.

Voice choice, timing, and lip sync

An AI dubbing voice should fit the speaker and remain easy to understand. A voice changer can alter pitch, tone, or perceived character, but that does not automatically preserve acting, emphasis, or pronunciation.

Lip sync tools try to align visible mouth movement with generated speech. They can help with a clear, front-facing speaker, but cuts, profile shots, covered mouths, and multiple speakers make the result harder to control. Review the full export instead of judging one short preview.

For presenter-led videos, a talking-avatar workflow can generate speech and facial movement together, which may be simpler than repairing an unrelated source video.

Free dubbing options and their limits

OptionUseful forLikely limit
Free online AI dubbing toolTesting one short clipCredits, duration, export quality, watermark, or sign-up
Free dubbing APITesting an integrationTrial credits, rate limits, or restricted voices
GitHub dubbing projectInspecting or adapting the pipelineYou operate the models, storage, and compute
Paid APIRepeatable production workflowsUsage-based billing and provider limits

Claims such as AI dubbing free unlimited, free no sign up, or AI video translator free unlimited need checking before you upload a long video. Unlimited may still hide fair-use rules, slower queues, export restrictions, or a limited set of voices.

API pricing may be calculated per execution, operation, rendered minute, generated credit, or model call. Rates and free allowances change, so check the provider's current pricing and usage rules.

Fixing dubbing sync

Fix AI dubbing sync at the earliest broken step. Check the transcript first, then the translation, speech length, segment timestamps, frame rate, and final audio offset. Moving the whole track will not fix individual sentences that are too long.

Reddit threads can reveal recurring symptoms, but a fix that worked for one tool may not apply to another. Record the failed segment, timing difference, model, and export settings before changing anything.

If captions drift as well, use the automatic-captioning workflow to inspect transcript timing before regenerating the dubbed audio.

Questions people ask

How do I turn off AI auto dubbing on YouTube?

Open the video's audio-track or language controls and select the original audio when that option is available. YouTube changes labels and availability across devices and releases, so update the app or try the desktop player if you cannot find the control.

How do I turn dubbing on or off on YouTube on a phone?

Open the video settings, look for an audio track or language option, and choose the original or dubbed track. The uploader must have supplied or enabled another track, and the exact menu can differ between the YouTube app, Shorts, and mobile web.

What is automatic dubbing on YouTube?

Automatic dubbing YouTube features create or serve translated audio tracks for eligible videos. Availability depends on the video, language, channel, account, and current YouTube rollout, so viewers will not see the same choices on every upload.

Is there a free AI video dubbing tool available?

Yes, some AI video dubbing apps and online tools offer a free tier or trial. Free use commonly limits credits, video length, voices, export quality, or commercial rights, and those terms can change.

Can I use an AI dubbing API for free?

Some providers offer trial credits, while GitHub projects may provide source code without hosted processing. A dubbing API free tier is not the same as free production: you may still pay for compute, storage, speech models, or usage after the trial.

How do I get dubbing AI to work?

Start with a clean source file and confirm the source language, target language, transcript, speaker selection, and output format. If the job fails, inspect the API response or job log before retrying.

How do I fix lip sync on YouTube?

First check whether the original file is already out of sync. If it is, correct the audio timing and export settings before uploading again; if only playback is affected, test another browser, device, or connection.

Is there a tool for AI dubbing with lip sync?

Yes, some dubbing tools combine translated speech with mouth-movement adjustment. Results depend on shot angle, speaker visibility, cuts, source quality, and the difference in sentence length between languages.

How can AI synchronization be used for video projects?

The German query “Wie kann Synchronisations-KI für Videoprojekte eingesetzt werden?” asks how AI can support video dubbing. You can use it to transcribe speech, translate dialogue, generate another voice track, align segments, and prepare versions for YouTube or other channels.

Wie kann ich ein Video mit KI synchronisieren?

Transkribiere zuerst den Originalton, übersetze den Text und erzeuge danach die neue Sprachspur. Prüfe Namen, Satzlänge, Timing und Lippenbewegungen, bevor du das fertige Video exportierst.

Welche App kann ich verwenden, um Videos zu synchronisieren?

Wähle eine App, die deine Quell- und Zielsprache, Sprechertrennung, Timing-Korrekturen und das benötigte Exportformat unterstützt. Für einen kurzen Test reicht oft eine Web-App; für wiederkehrende Abläufe ist eine API meist leichter zu automatisieren.

Wie funktioniert die Synchronisation bei Filmen?

Bei klassischer Filmsynchronisation wird der Dialog übersetzt, für Timing und Mundbewegungen angepasst, eingesprochen und anschließend mit Musik und Geräuschen gemischt. AI dubbing can automate parts of that process, but dialogue choices and final quality still need review.

Are Speechify and other free dubbing tools suitable for long videos?

Check the current duration, credit, export, and commercial-use limits before uploading a long video. “Long video dubbing AI free” and “YouTube video dubbing AI free” offers may be useful for testing, but free allowances and product features change.

Make your dubbing look real

Bring your footage and your new-language audio — the Video Lip Sync API re-aligns the mouth so the dub looks natural. Documented, webhook-ready, built for your pipeline.

Browse the lip-sync and dubbing models on the model catalog →

New to this? Read AI video dubbing without a studio →