Lipsmatch What is AI dubbing
Updated
What is AI dubbing?
How it works, the 3 kinds, where it goes wrong and how to check a dub before it goes live.
The short answer
AI dubbing uses software to put a video into another language. It turns the speech into text and translates it. Then a synthetic voice or the speaker's recreated voice speaks it. Some services also change the mouth to match. It works best when a person checks the translation and the result.
Lip-synced dubbing on a Britannia film
This is a Britannia Good Day campaign film. Tap Original to hear the client's Bengali dub over the mouth as shot. Tap Lipsmatch, and the lips follow every Bengali word.
What AI dubbing means
Dubbing replaces the speech in a video with speech in another language. In a traditional dub, a studio casts actors who record each line while they watch the picture. AI dubbing does the same job with software, from the first transcript to the final voice.
The simplest tools read the translation in a stock synthetic voice. Others recreate the voice of the person on screen, so viewers hear a voice they already know. Some go one step further and change the mouth, so the lips form the new words.
It is now part of everyday video. Prime Video tested AI-aided dubbing on 12 licensed titles. Coursera dubbed more than 100 of its courses this way. It kept each speaker's own voice and matched the lips.
Large publishers still have people check the work. Amazon calls its test a hybrid. In it, language professionals check the quality. TED says that human translators review every dubbed talk. Nothing goes live until they approve it.
How AI dubbing works, step by step
Most AI dubbing runs through the same 6 steps. Services differ in how many of them a person checks.
- Transcribe. Speech recognition writes down every word and notes who speaks when. Music, accents and people talking over each other cause the first errors.
- Translate. Machine translation turns the transcript into the new language. A good translation keeps names as the speaker says them. It keeps the meaning of jokes and idioms. It also keeps each line close to its original length.
- Make the voice. A synthetic voice reads the translation. It is a stock voice, or a recreation of the speaker's own voice built from their recordings.
- Fit the timing. Each new line has to fill about the same time as the original line. Research on automatic dubbing treats this as a core rule, because the pauses and cuts stay where they are.
- Match the mouth. This step is optional. Lip sync reshapes the lips in each frame to fit the new audio. Without it, the lips keep moving in the original language.
- Check and mix. The new voice goes back under the music and effects. Then a person who speaks the language watches the whole video and fixes what sounds or looks wrong.
The 3 kinds of AI dubbing
Each kind changes a little more of the video. The first swaps the voice for a synthetic one. The second keeps the speaker's own voice. The third also changes the mouth to match.
| Question | AI voice-over | Voice recreation | Lip-synced dubbing |
|---|---|---|---|
| What changes | The sound | The sound | The sound and the mouth |
| The voice | A stock synthetic voice | The speaker's own voice, recreated | Usually the speaker's own voice, recreated |
| The mouth | Moves in the original language | Moves in the original language | Forms the new words |
| What it needs | The video and a checked translation | Clean recordings of the speaker, and approval for that voice | All of that, plus approval for the face on screen |
| What to check | The translation and the pronunciation | The translation and how close the voice sounds | The translation, the voice and every close-up |
| Cost | Lowest | Higher | Highest |
| Best for | Training, screen recordings and narration over pictures | Lessons and talks where viewers know the voice | Ads, films, close-ups and anyone talking to camera |
| Where you see it | Self-serve apps that read a script in a stock voice | Services that recreate the voice and leave the mouth as filmed | Lipsmatch, on aired national campaigns, and some large talk and course platforms |
Swipe the table sideways to see every column.
Is AI dubbing good?
AI dubbing is good enough for many videos. It is at its best when a person checks it. Its weak points are well known: names, idioms, strong accents and a delivery that sounds flat.
A person can fix each of those in the translation or in the final check, before anyone watches. That is why the same software can give a careless dub or a careful one.
Human dubbers show what matters most. Researchers studied 319.57 hours of dubbing from 54 professionally dubbed titles. The dubbers put natural delivery and a faithful translation first, and strict limits on line length and lip movement second. A careful review of an AI dub starts with the same 2 things.
A familiar voice helps too. In a small 2025 study, 18 students compared several lecture formats, subtitles among them. 14 of them liked a dub in the teacher's recreated voice best. Students and teachers there found a mismatch between lips and sound annoying. One student said that good sync felt natural.
Where AI dubbing goes wrong, and how checking fixes it
Most errors come from the same 6 places. A person who speaks the language can fix each one before anyone watches.
- Names and terms. Software guesses at brand names, places and technical words. A word list and a checked translation keep each one as the speaker says it.
- Jokes and idioms. A word-for-word translation keeps the words and loses the meaning. A good translator keeps the meaning. If the joke itself must change for a new market, that new line comes from you or your agency.
- Flat delivery. A synthetic voice can sound calm in a tense scene or slow in a funny one. A person compares each line with the original take and asks for the same energy.
- Lines that run long. A study of 8 languages read aloud found that English packs the most information into each second. A line translated from English often needs more time. A good translation keeps the meaning in fewer words.
- A mouth in the wrong language. A sound-only dub leaves the lips moving in the original language. Viewers see it in every close-up. Lip sync fixes this in the picture itself.
- Several speakers. Software can lose track of who speaks when. Then it gives a line to the wrong voice. A transcript with each speaker's name on their lines keeps every voice in its place.
Other ways to put a video in a new language
Each method fits a different kind of video. Choose by how your viewers watch and how much of the face they see.
Subtitles are the cheapest choice, and viewers still hear the speaker's real voice. They suit short posts, videos played with the sound off and viewers who read quickly.
A voice-only AI dub suits narration, slides and screen recordings, where no mouth is on screen. It costs less than a version with the mouth matched.
A studio dub with actors suits a feature film that wants a new performance in each language. Lip-synced dubbing suits ads, lessons and anyone who speaks to camera, because viewers watch the face.
Our guide to subtitles, voice-over and dubbing sets these methods side by side.
How to judge an AI dub before you publish
Watch the dub the way a new viewer will. These 5 checks catch most problems.
Quality check
Ask a native speaker
Ask someone who grew up with the language to watch it. They hear a wrong word or a stiff phrase at once.
Check every name
Listen for each name, brand and number. A person must check these words one by one.
Compare the energy
Play a funny line and a serious line next to the original. The new voice must rise and fall in the same places.
Watch the close-ups
Watch at full size on a large screen. Look at the mouth on side angles, fast moves and hands near the face.
Check the timing
Each line must start and end with the cut and the gesture. A line that sounds rushed or runs past the cut needs a shorter translation.
How Lipsmatch does AI dubbing
Lipsmatch makes the third kind in the table above. We change the mouth so it speaks the new language, and our team checks every version before delivery.
There are 2 ways to start. If you already have a dub in any language, from any studio, bring it. We match the speaker's mouth to each word, frame by frame. Or leave the dub to us. We translate the script you send and check it line by line. Then our technology recreates the speaker's own voice. That voice reads the translation with the energy of the original take. Last, we match the mouth to that voice.
You get each language as its own finished video file. It goes up as a separate upload, for example on a language channel, in a playlist or on your website. Our page for YouTube creators shows how.
We take on a video only with the approvals you already have for each speaker in it. Our record on aired campaigns is 12 languages and 75+ broadcast masters. Teams that publish often can agree on the hours and the languages once, on a monthly plan. They then get their videos in the new languages in regular batches.
AI dubbing questions
What is the difference between dubbing and translation?
Translation changes the words from one language into another, often as subtitles or a written script. Dubbing replaces the speech you hear with speech in the new language, timed to the picture. AI dubbing does both with software. It translates the script, then speaks it in a synthetic or recreated voice.
What is Lipsmatch?
Lipsmatch is AI lip sync for films, ads and talks. The speaker's own voice, recreated by our technology, speaks the new language, and the mouth matches every word. It is the step after the dub: the picture changes too, so viewers see the new language as well as hear it.
Can AI dubbing clone my voice?
Yes. Many services can recreate your voice from clean recordings of you speaking. Your translated words then play in a voice that sounds like yours. At Lipsmatch, we call this recreating a voice. We do it only with the approvals you already have for that voice. Our guide to your own voice in another language explains what it needs.
Does AI dubbing work for Indian languages?
Yes. Lipsmatch shipped 12 languages on aired campaigns. All of them except English are Indian: Hindi, Bengali, Tamil, Telugu, Malayalam, Punjabi, Marathi, Gujarati, Kannada, Odia and Assamese. In each one, someone who speaks the language must check the translation. Then names and local words come out right.
Do I need to label an AI dubbed video?
It depends on the platform and the country. YouTube lists a dub in your own recreated voice among the uses that need no disclosure. You must disclose a video that makes a real person appear to say or do something they did not. India's IT rules add label duties from 20 February 2026. The EU AI Act adds them from 2 August 2026. Read our guide to the rules, and ask a lawyer about your case.
How much does AI dubbing cost?
It depends on how much of the work people do. Self-serve tools cost the least, because you check the result yourself. Services usually price by the minutes of finished video and the number of languages. A recreated voice and a matched mouth add work, so they cost more. For Lipsmatch, ask us for a quote, or read what sets the price of dubbing.
Is YouTube's auto dubbing the same as AI dubbing?
Yes. It is AI dubbing in a synthetic voice, added to the video as a sound track. Lipsmatch is the third kind in the table above: the speaker's own recreated voice, with the mouth matched to every word. A sound track leaves the picture as it was. So the mouth still forms the original words. That is why a lip-matched version goes up as a separate video.
Explore related
Try AI dubbing on one scene
Send one scene with a face in close-up. We send it back in your language, with the mouth matched, at no cost and with no commitment. A link to the file is enough.