Free Online Audio Converter (No Upload)
xFormat converts audio between MP3, WAV, FLAC, M4A, OGG and AAC inside your browser, so your music and recordings are processed on your device and never uploaded.
Runs in your browser — files never leave your device.
How it works
Pick a song, voice memo or recording, choose the format your player or editor wants, and convert. It runs locally, so there are no upload limits and no queue.
- 1
Select an audio file.
- 2
Choose the target format: MP3, WAV, FLAC, M4A, OGG or AAC.
- 3
Click Convert and download the new file.
Lossy or lossless: what the formats mean
MP3, AAC (and M4A, which usually holds AAC) and OGG are lossy: they discard sound details you are unlikely to hear in return for small files. WAV and FLAC are lossless: WAV is uncompressed and big, while FLAC is compressed without losing anything and is typically around half the size of WAV.
Direction matters. Going from a lossless file to a lossy one makes it much smaller with minimal audible difference at a good bitrate. Going the other way, say MP3 to FLAC, only wraps the existing sound in a bigger file and does not restore what was thrown away.
Which target for which job
Use MP3 for maximum compatibility, M4A or AAC for Apple devices and efficient small files, OGG for games and some open-source players, WAV for editing software, and FLAC for archiving a collection. For lossy outputs you can pick 128, 192, 256 or 320 kbps: 192 kbps is a reasonable default for music and 128 kbps works for speech. OGG output uses the Opus codec.
Decoding uses your browser's built-in decoders. MP3 is encoded by a small built-in encoder (about 300 KB), other formats by the browser's own encoders where available. Files or formats the browser cannot handle switch to compatibility mode, a one-time download of about 31 MB, which writes OGG as Vorbis.
Frequently asked questions
Which audio formats can I convert between?
MP3, WAV, FLAC, M4A, OGG and AAC.
Does converting reduce audio quality?
Converting to a lossy format such as MP3 or AAC discards some detail, but at 192 kbps or higher it is hard to hear. Converting to WAV or FLAC does not remove quality, but it cannot restore what an earlier lossy file lost.
Are my audio files uploaded?
No. The conversion runs in your browser and the files stay on your device.
Is there a file size limit?
There is no server limit. Practically, about 500 MB on desktop and about 200 MB on phones, since browsers have limited memory.
Can I use it on iPhone or Android?
Yes. It works in mobile browsers without installing an app.