Online Audio Format Converter

Convert between MP3, WAV, FLAC, AAC, OGG, and M4A while preserving source quality. Compatible with every device — iOS, Android, Windows, Mac, car head units, Bluetooth speakers.

Select output format
Choose the format that matches your device or software.

About this audio format converter

Every device prefers a different format. iPhones default to M4A, older car head units only read MP3, audiophile DAPs need lossless FLAC, and internet radio uses low-bitrate AAC to save bandwidth. OneAudio Converter uses FFmpeg to switch between the six most common formats without needing to install anything.

For lossless formats (WAV, FLAC), quality is preserved 100% — a FLAC converted to WAV sounds identical. For lossy formats (MP3, AAC, OGG), default bitrate is 192kbps — a sweet spot between file size and quality. Converting lossy → lossless does NOT improve quality (lost data can't be recovered); only go the other way.

  • Supports MP3, WAV, FLAC, AAC, OGG, M4A — the six most popular formats
  • Lossless → Lossless preserves 100% quality
  • Default 192kbps for MP3/AAC/OGG — great for most ears
  • Source sample rate preserved (44.1kHz / 48kHz)
  • Stereo / mono / 5.1 preserved
  • Server-side, 5-15s for a 10MB file

Convert MP3 to WAV, FLAC, or M4A online

  1. 1

    Upload your source audio file

    Drop in an MP3, WAV, FLAC, AAC, OGG, or M4A — OneAudio auto-detects the source format.

  2. 2

    Pick an output format

    Open the dropdown and pick your target. Rule of thumb: MP3 for universal playback, FLAC for audiophile listening, M4A for iPhone.

  3. 3

    Click Start and download the converted file

    Conversion takes 5-30 seconds depending on length. Click DOWNLOAD to grab the result.

Real uses of audio format conversion

MP3 → WAV for video editing
Pro editors (Premiere, DaVinci) prefer WAV — no generation loss across multiple re-renders.
FLAC → MP3 for the car
Most older car units only read MP3. Convert FLAC to 192kbps MP3 — good quality, 5× smaller.
AAC/M4A → MP3 for ringtones
iPhone accepts M4A ringtones, Android usually wants MP3. One conversion to keep both happy.
WAV → FLAC to save disk
FLAC losslessly compresses WAV by 40-50% — same quality, much smaller library.

Frequently asked questions about audio conversion

Does MP3 to FLAC improve quality?
No. MP3 is lossy — information is already gone. Wrapping it in FLAC makes the container lossless but can't restore the lost data.
What's the best format for music?
FLAC if you have high-end headphones/speakers and want top quality. 320kbps MP3 is indistinguishable from FLAC for most listeners.
Are M4A and AAC the same?
M4A is a container, AAC is the codec inside. Most M4A files are AAC. Going M4A → AAC usually just renames the file without re-encoding.
Is 192kbps high enough?
Good for 95% of use cases — higher than tape-era CD rip bitrates (128kbps). For album masters, go 320kbps or FLAC. For regular podcasts, 128kbps is fine.
Can I convert video to audio here?
Yes, but the dedicated Audio Extractor is better suited for video → MP3 conversion.
Why is my FLAC 5× bigger than the MP3?
FLAC is lossless, MP3 is lossy — FLAC keeps 100% of the data so it's larger. It's the usual quality-vs-size trade-off.