What happens when you convert MPEG to AAC
- AAC holds sound only, so the picture is discarded and the soundtrack is encoded as AAC at 192 kbps in an ADTS stream.
- If the MPEG has several audio tracks, the first one is used.
How to convert MPEG to AAC online
- Press "Choose MPEG files" and select one or more files, or drag them onto the box. You can add files of any size your device can hold in memory.
- Adjust the settings if you need to: the bitrate controls quality and size. The defaults suit most people.
- Press "Convert to AAC". The first audio or video conversion downloads the converter engine, about 32 MB, which your browser then keeps for next time.
- Save each AAC with its download button. Close the tab and every trace of the files is gone from memory.
Why convert MPEG to AAC?
MPEG files usually come from DVD-era video, Video CDs and older camcorders. People convert them to AAC because raw AAC streams are what some broadcasters, podcast tools and hardware players ask for.
In short, MPEG is good at what it was made for, and AAC is the more practical choice when the file has to play on another device or app. MPEG does not play in most browsers; plays in VLC and desktop players, while AAC plays in all current browsers and on Apple and Android devices.
How to convert MPEG to AAC on Windows, Mac, iPhone and Android
On Windows
Open this page in Chrome, Edge or Firefox, drag your MPEG files in from File Explorer, and press Convert. Each AAC is saved to your Downloads folder. If you prefer a desktop program, VLC can also convert MPEG to AAC: choose Media, then Convert / Save.
On a Mac
Safari, Chrome and Firefox all work. Drag the MPEG files from Finder onto the drop zone and the AAC files land in Downloads.
On iPhone and iPad
Open the page in Safari and tap Choose MPEG files. You can pick from Photos or from the Files app. The converted AAC appears in Files, in the Downloads folder.
On Android
Open the page in Chrome, tap Choose MPEG files and pick them from Files or your gallery. The AAC is saved to the Download folder, where any file manager can find it. Keep the screen on while a long video converts, because Android may pause a tab in the background.
Best settings for MPEG to AAC
AAC is a lossy format, so the bitrate decides both the sound quality and the file size. Size grows in a straight line with bitrate: double the bitrate and the file doubles.
| Bitrate | Size per minute | Good for |
|---|---|---|
| 320 kbps | about 2.4 MB | the highest quality, for music you will keep |
| 256 kbps | about 1.9 MB | excellent music quality |
| 192 kbps | about 1.4 MB | the default: transparent for most listeners |
| 128 kbps | about 1.0 MB | good for music on the go and for podcasts |
| 96 kbps | about 0.7 MB | speech and audiobooks |
| 64 kbps | about 0.5 MB | voice notes and spoken word only |
The MPEG was already compressed, so pick a bitrate at least as high as the original. Going higher does not add quality back, it only makes the file bigger.
MPEG vs AAC: the differences
| MPEG | AAC | |
|---|---|---|
| Full name | MPEG-1 or MPEG-2 video | Advanced Audio Coding |
| Type | video | audio |
| Created by | the Moving Picture Experts Group | the Moving Picture Experts Group |
| First released | 1993 | 1997 |
| Compression | Lossy | Lossy |
| Usually contains | MPEG-1 or MPEG-2 video with MP2 audio | AAC audio in a raw ADTS stream |
| In a browser | does not play in most browsers; plays in VLC and desktop players | plays in all current browsers and on Apple and Android devices |
| Common uses | DVD-era video, Video CDs and older camcorders | iTunes and Apple Music, YouTube audio and streaming |
| MIME type | video/mpeg | audio/aac |
About MPEG and AAC files
What is an MPEG file?
MPEG-2 is the video format of DVDs and broadcast TV. It needs roughly twice the bitrate of H.264 for the same picture, so converting to MP4 usually shrinks the file a lot.
What is an AAC file?
AAC was designed as the successor to MP3 and sounds better at the same bitrate, especially below 128 kbps. A bare .aac file is a raw stream with no chapters or cover art; the same audio in a container is usually called M4A.
MPEG to AAC not working? Common problems
- The conversion is slow. Audio and container changes take seconds, but re-encoding video runs on your own processor. Lower the resolution to 720p, close other tabs, and keep the device plugged in.
- The tab stops or reloads on a very large file. Browsers limit how much memory one tab can use, around 2 GB and less on phones. Split long recordings or convert them on a computer.
- Song titles are missing. Tags such as title and artist are copied when AAC can store them, but cover art is not carried over.
Convert MPEG to AAC with ffmpeg
This converter runs ffmpeg inside your browser. If you would rather use the ffmpeg command line on your own computer, this command produces an equivalent AAC with the same kind of settings:
ffmpeg -i input.mpeg -vn -c:a aac -b:a 192k -f adts output.aacReplace input.mpeg with the name of your file. For a whole folder of MPEG files, run the command in a loop, or drop them all on the converter above, which processes them one after another.
MPEG to AAC converter FAQ
Will I lose quality converting MPEG to AAC?
The sound is re-encoded as AAC at 192 kbps in an ADTS stream, which is transparent for most listeners. The picture is not kept.
Why is the AAC a different size from the MPEG?
The AAC is much smaller, because the video stream, usually most of the file, is dropped.
Are my MPEG files uploaded anywhere?
No. The conversion runs inside this browser tab using ffmpeg compiled to WebAssembly, so your files stay on your device. You can disconnect from the internet after the page and converter engine have loaded and it still works.
Can I convert several MPEG files to AAC at once?
Yes. Select or drop as many files as you like; they are converted one after another and each gets its own download button.
How do I open an AAC file?
AAC plays in all current browsers and on Apple and Android devices. AAC is common for iTunes and Apple Music, YouTube audio and streaming.
Is this MPEG to AAC converter free?
Yes. There is no sign-up, no watermark and no limit on how many files you convert. The site is paid for by advertising, and because conversions run on your device there is no server cost per file.
Can I convert MPEG to AAC on my phone?
Yes. The converter works in Safari on iPhone and iPad and in Chrome on Android. Converted files are saved to the Downloads folder.