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AC3 converter

Convert Dolby Digital (AC3) audio tracks to MP3 or WAV.

Free & unlimited
All processing happens in your browser — files never leave your device. The audio engine loads once from a CDN.

AC3, better known as Dolby Digital, is the surround audio format used on DVDs, in broadcast television and in home cinema. It arrives as a standalone .ac3 file when someone demuxes a DVD or extracts a soundtrack, and at that point almost nothing outside media-player software will open it. This converter decodes AC3 in your browser and re-encodes it as MP3 for playback anywhere or WAV for editing. Bitrate runs from 128 to 320 kbps for MP3, the sample rate can be matched or forced to 44.1 or 48 kHz, and batches come back as a ZIP. The important thing to know before you start is what happens to the surround channels.

Key facts about AC3 converter

Key facts about AC3 converter
What AC3 isDolby Digital, the surround codec used on DVD, in ATSC and DVB broadcast, and in home-cinema systems
Channel countAC3 is commonly 5.1 — six channels. MP3 is stereo, so a surround source is downmixed during conversion
What downmixing costsCentre-channel dialogue and surround effects are folded into two channels; the spatial placement is gone and cannot be recovered
Native sample rateAC3 on DVD is 48 kHz. Leaving sample rate on auto avoids an unnecessary resample
Typical DVD bitrate384 or 448 kbps across six channels, which is roughly 64 to 75 kbps per channel
Output formatsMP3 for playback anywhere, WAV for editing — those are the two offered here
Lossy to lossyAC3 is lossy, so an MP3 output costs a second generation; WAV adds no further loss
Bitrates128, 192, 256 and 320 kbps for MP3; default 256
BatchConvert several .ac3 files at once and download them as a ZIP built in the browser
Size cap200 MB per file, which covers a full-length feature soundtrack

What happens to your file

The decode and re-encode run on ffmpeg compiled to WebAssembly in a Web Worker inside this tab. Your AC3 files go into that worker's in-memory filesystem and the results come back as blobs; the batch ZIP is built in the browser. Nothing is uploaded and no copy is stored. The one network request is the first-time download of the ffmpeg core, about 32 MB of fixed public code from the jsDelivr CDN, cached by your browser and reused by every audio tool here — it carries no part of your file.

About this tool

  1. 1

    Add your AC3 files

    Drop .ac3 files, up to 200 MB each. Demuxed DVD tracks and broadcast captures are the usual sources.

  2. 2

    Choose MP3 or WAV

    MP3 for a file you want to play on a phone or in a car. WAV if the audio is going into a video edit or an audio editor, where you do not want a second lossy generation.

  3. 3

    Set the bitrate

    256 kbps is the default and a sensible match for a DVD-rate AC3 once it has been folded to stereo. 320 buys little; 128 is enough for dialogue-only material.

  4. 4

    Leave sample rate on auto

    DVD AC3 is 48 kHz. Forcing 44.1 kHz adds a resample with no benefit unless the destination specifically needs CD rate.

  5. 5

    Convert

    Files process one at a time with per-file progress. The summary shows exactly what is being applied.

  6. 6

    Download

    Individually or as a ZIP, ready for the software or device that would not open the AC3.

Specs & compatibility
InputAC3 (.ac3), up to 200 MB per file
Output formatsMP3 and WAV
Bitrates128, 192, 256 or 320 kbps for MP3, default 256
Sample ratesAuto (match source), 44,100 Hz or 48,000 Hz
ChannelsMultichannel AC3 is downmixed to stereo by the encoder; there is no surround output option here
Batch outputIndividual downloads or one client-side ZIP
EngineSingle-threaded ffmpeg.wasm 0.12.10 with the native AC3 decoder
BrowsersChrome, Edge, Firefox and Safari 15+ — no browser plays AC3 natively, which is why conversion is needed
  • Understand the downmix before you convert. A 5.1 AC3 becomes two channels, and once the centre and surround content is folded in, the separation is gone permanently.
  • Dialogue lives in the centre channel on a film soundtrack. After a downmix it sits in the phantom centre of the stereo image, which usually works fine but can sound quieter relative to effects.
  • Convert to WAV rather than MP3 when the audio is going into a video edit — that way the only lossy step is the one already in the AC3.
  • Leave sample rate on auto. DVD audio is 48 kHz, which is also the video standard, so there is rarely a reason to change it.
  • 256 kbps MP3 is a comfortable match for a downmixed 448 kbps AC3. Higher bitrates store the same downmix in a larger file.
  • If you need to keep the surround channels, this is the wrong tool — a desktop application that can write multichannel FLAC or AAC is what that job requires.
  • A whole film's AC3 track is usually well under 200 MB, so the size cap is rarely the limiting factor here.
  • Decodes Dolby Digital AC3 in the browser
  • MP3 and WAV output
  • MP3 bitrate from 128 to 320 kbps
  • Sample rate matched to source or forced
  • Batch conversion with per-file progress
  • ZIP download for multiple files
  • In-page playback of the converted audio
  • Playing a demuxed DVD soundtrack on a phone
  • Getting an AC3 audio track into a video editor as WAV
  • Converting a broadcast capture's audio for archiving
  • Extracting a film score from a DVD audio track for personal listening
  • Making home-cinema audio files playable on a portable device
  • Preparing AC3 dialogue for transcription software that needs WAV
They are downmixed to stereo, because both output formats here are two-channel. A 5.1 AC3 has front left and right, centre, low-frequency effects and two surround channels; the encoder folds them together using standard downmix coefficients so nothing is lost outright, but the spatial separation is. Centre-channel dialogue ends up in the phantom centre between your speakers, and surround effects join the front image. This is irreversible — the stereo file cannot be un-mixed back into 5.1.
WAV if the audio is going into editing software, a video project or a transcription tool. It is uncompressed, so the only lossy step in the chain is the one AC3 already applied, and nothing further is added by later processing. MP3 if you simply want to listen — on a phone, in a car, on a player that will not open AC3. MP3 costs a second lossy generation but produces a file roughly a tenth the size, which is usually the right trade for playback.
256 kbps is the default and a good match. A DVD AC3 track typically runs at 384 or 448 kbps spread across six channels, which is around 64 to 75 kbps per channel — after downmixing to two channels, a 256 kbps stereo MP3 comfortably carries what survived. Going to 320 mostly stores the same downmix in a larger file. For dialogue-heavy material such as a commentary track, 128 kbps is perfectly adequate.
Because AC3 was designed to live inside a container — a DVD's VOB, a broadcast transport stream, an MKV — rather than as a standalone file. When it is demuxed out on its own, a lot of software does not recognise the bare stream even if it could decode AC3 in context. No browser plays it natively either. Media players such as VLC handle it happily; almost everything else, from phone music apps to car stereos, does not.
Yes. Drop as many .ac3 files as you like and they convert in sequence with per-file progress, using the same format, bitrate and sample rate settings. You can download each result on its own or take the whole set as a ZIP, which is assembled inside your browser from the converted blobs. Because everything stays in memory, a large batch is limited by your device rather than by any server-side quota or queue.
No. The AC3 decode and the MP3 or WAV write are performed by ffmpeg compiled to WebAssembly, running in a Web Worker on your own machine. Your file goes into that worker's in-memory filesystem and the result comes back as a blob in your tab; the batch ZIP is built in the browser too. The only network request is the one-time fetch of the ffmpeg core, about 32 MB of fixed public code from the jsDelivr CDN.

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