MP3 to AC3 converter
Convert MP3 to AC3 in your browser. No upload and no account: the file never leaves your device, so the only size limit is your device’s memory.
Fit Meter
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Bytes of your files sent anywhere: 0 B · nothing leaves this tab
Every request this page makes is listed as it happens. You’ll see our own code loading, and for some formats a codec engine, but never your file going out.
- Waiting for network activity…
Check it yourself: open your browser’s developer tools on the Network tab, or turn off Wi-Fi once the page has loaded. The tools keep working.
Related conversions
Need it the other way round? Convert AC3 to MP3Read more about the MP3 format and the AC3 format, or see every audio tool and all audio conversions.
Should you convert MP3 to AC3?
Fine when a player or app needs AC3. Converting between two lossy formats compresses the sound a second time, so match or exceed the original bitrate to keep the loss inaudible.
MP3 is the most compatible lossy audio format ever made; AC3 is Dolby Digital surround sound from DVDs and TV. Use AC3 for soundtracks going to DVD authoring or a home cinema system.
How to convert MP3 to AC3
- 01
Add your MP3
Drop your MP3 file onto the box, or click to choose it. It is read from your disk and stays there.
- 02
Check the settings
The output is already set to AC3. Change the bitrate if you want to; the defaults suit most files.
- 03
Save the AC3
Press convert and save the AC3. Several files come back together as a ZIP.
What changes when MP3 becomes AC3
Two rounds of compression
Each lossy encode throws away a little more. A MP3 at 128 kbps converted to AC3 at 192 kbps sounds like the original; converted at 96 kbps it can turn swirly and dull.
Surround channels
AC3 keeps up to 5.1 channels, so surround sources stay surround. Stereo sources are written as stereo.
Expect a larger file
AC3 generally takes more room than MP3. If the file has to fit an upload limit, check the size once it’s converted. MP3: About 1 MB a minute at 128 kbps, 2.4 MB at 320 kbps. AC3: About 3.4 MB a minute at 448 kbps.
This page is put together from our notes on each format, choosing only what is true of MP3 and AC3, so every pairing states the same facts the same way. How these pages are made.
Why it doesn’t upload
Recordings are often private: interviews, voice notes, unreleased music. Your browser can decode and encode audio itself, so there is no reason to send it anywhere.
How to check for yourselfWorth knowing
- About the MP3. Converting a low-bitrate MP3 to 320 kbps makes it bigger without making it sound any better; what was thrown away is gone.
- About the AC3. Converting a 5.1 AC3 to a stereo format mixes it down; dialogue that lived in the center channel can end up quieter.
- MP3, WAV, M4A, OGG, Opus and FLAC are converted by your browser directly. WMA, AMR, APE, AC3 and the other specialist formats use the FFmpeg engine, a one-time 31 MB download.
Questions
Does converting MP3 to AC3 lose quality?
AC3 is lossy, so a little is discarded, but at the default bitrate the difference is inaudible for nearly everyone.
Will an AC3 play in my car or on my phone?
AC3 has patchy support: home cinema receivers, TVs, VLC and video editors; phones and browsers often can’t.
Read more about this
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