AAC to MP3 Converter
Convert AAC and M4A audio files to MP3 format instantly in your browser — no uploads, no accounts, no waiting. Supports batch conversion of multiple files. Choose output quality from 64 kbps up to 320 kbps.
Conversion Result
FAQ
What is the difference between AAC and MP3?
AAC (Advanced Audio Coding) is a newer codec than MP3 and generally produces better audio quality at the same bitrate. It is the default format for Apple devices (iPhone, iPad, iTunes), YouTube, and Android. MP3 is the most universally supported audio format — compatible with virtually every device, car stereo, speaker, and audio editing software. Converting AAC to MP3 is useful when you need maximum compatibility across older or non-Apple devices.
Will I lose audio quality converting AAC to MP3?
Yes — both AAC and MP3 are lossy formats, so converting between them introduces some additional quality loss ("generation loss"). To minimise this, always choose the highest output bitrate (320 kbps). If your original AAC was 128 kbps, outputting at 320 kbps won't improve quality but also won't make it worse. For archival purposes, always keep your original AAC files.
Is my audio uploaded to a server?
No. This tool uses your browser's native Web Audio API and MediaRecorder API to decode and re-encode your audio entirely within your browser tab. Your AAC files never leave your device and nothing is sent to Alfreto's servers.
What bitrate should I choose?
320 kbps — highest quality, largest file. Use for music archiving or when quality is critical. 192 kbps — excellent quality, imperceptible difference for most listeners. Recommended for general music use. 128 kbps — standard quality, good for streaming and casual listening. 96 kbps — acceptable for podcasts and speech. 64 kbps — small file, suitable for voice-only content.
What is M4A and is it the same as AAC?
M4A is a file container (MPEG-4 Audio) that typically contains AAC-encoded audio. Think of M4A as the "box" and AAC as the audio "content" inside. This tool converts both .aac and .m4a files automatically. Most audio from iTunes or Apple Music is in M4A/AAC format.
Can I convert multiple AAC files at once?
Yes. This tool supports batch conversion — select multiple files at once (hold Ctrl or Cmd while clicking), or drag and drop multiple files. Each file is converted sequentially and you can download them all at once as a ZIP archive.
Is there a file size limit?
There is no enforced file size limit. However, very large files (over 200 MB) may be slow on devices with limited RAM. Modern computers typically convert audio significantly faster than real-time, so a 10-minute audio file usually converts in under 30 seconds.