MP3 to AAC
Convert MP3 audio to AAC — smaller, Apple- and YouTube-ready files, right in your browser, nothing uploaded.
Drag & drop your MP3 files here, or click to choose. Everything runs in your browser — nothing is uploaded.
AAC (Advanced Audio Coding) is a lossy audio format designed as the successor to MP3, packing the same sound into a smaller file at any given bitrate and serving as the native audio standard on Apple devices, iTunes, Apple Music and YouTube. People convert MP3 to AAC to shrink a music library or to make files play cleanly across modern phones and apps. This free MP3-to-AAC converter re-encodes your files entirely in your browser using a WebAssembly build of FFmpeg, so nothing is ever uploaded. Choose a bitrate, drop in one or many MP3 files, and each one converts automatically — then preview and download every result. No signup, no watermark, no install.
Frequently Asked Questions
How do I convert MP3 to AAC?
To convert MP3 to AAC, choose a bitrate if you want to, then drag your MP3 files onto the drop area or click to choose them, and each file is re-encoded to AAC automatically the moment it is added, with no format to pick and no convert button. When a file finishes it appears as a row showing the new name and size, an inline player to preview it, and a Download button to save it.
Is it free and private?
Yes, the tool is completely free with no signup, no watermark and nothing to install, and every conversion runs inside your browser through a WebAssembly build of FFmpeg, so your MP3 files are never uploaded to any server or seen by anyone else. That privacy holds no matter how many files you convert, which makes it safe even for private recordings or unreleased music.
Will converting MP3 to AAC improve the sound quality?
No, because your MP3 is already a lossy file, converting it to AAC cannot restore any of the detail that was discarded when the MP3 was first encoded; the tool only re-packs the sound that is already there into the AAC format. Since AAC is more efficient than MP3, it can hold that same sound at an equal or lower bitrate, and keeping the bitrate at 192 kbps or higher keeps the difference from the original hard to hear.
Why convert MP3 to AAC?
AAC is the successor to MP3 and stores the same audio in a smaller file at a given bitrate, so people convert to it to save space without an obvious drop in quality, and because it is the native audio format on Apple devices, iTunes and Apple Music. AAC is also the standard audio format for YouTube, so it plays smoothly across modern phones, apps and browsers.
Which bitrate should I choose?
For most music the default 192 kbps offers a good balance of quality and file size, so it is the recommended choice; pick 256 or 320 kbps to stay as close to the source MP3 as possible, or drop to 128 or 96 kbps when you want the smallest files. Set the bitrate before you add files, because it is read at the moment each file converts, and going above the source MP3's bitrate will not add quality back, only size.
Is there a file size or number limit?
There is no fixed size or count limit, so you can drop many MP3 files at once and each is converted separately and listed with its own preview player and Download button, which makes batch conversion quick with nothing queuing on a server. Because the work happens on your own device, very large files of several hundred megabytes convert more comfortably on a desktop or laptop than on a phone.
Does it work on iPhone, Android and every browser?
Yes, it works in any modern browser on Windows, Mac, Linux, iPhone and Android, with nothing to install and no account needed, so you can convert MP3 to AAC on a laptop or straight from your phone whenever you need to. The first time you use it, a one-time converter of about 32 MB downloads and is then cached, so every conversion after that starts instantly.