Audio Converter Online — MP3, WAV, M4A
Convert audio between MP3, WAV, M4A. In your browser, no upload. Bitrate, mono/stereo, sample rate options. Free.
Drop audio files here or choose them
MP3, WAV, M4A, AAC, OGG, FLAC, OPUS, WebM — multiple files at once
About this audio converter
A universal online audio converter that runs entirely in your browser. Drop one or several files in any common format — MP3, WAV, M4A (iPhone AAC), OGG, FLAC, OPUS or WebM — and get the result in your chosen output format. Files never leave your device.
Available outputs are MP3 (via the lamejs library, bitrates 128/192/256/320 kbps) and WAV (16-bit lossless PCM). You can change channel count (mono / stereo) and sample rate (44.1 kHz CD-quality, 48 kHz video standard, or keep original). Multiple files are downloaded as a single ZIP archive.
No sign-up, no upload to a server, no watermarks. Works on desktop, tablet and phone — Safari on iPhone and Chrome on Android both support the Web Audio API, which decodes all common audio formats.
Where it helps
Voice memo to MP3
Convert M4A or AAC from your iPhone, Android voice recorder, or Zoom recording into a regular MP3 — easy to send in chat, attach to email, or upload to a podcast platform.
FLAC → MP3 for portable players
Shrink your library 5-10×: compress lossless FLAC into MP3 at 320 kbps — practically indistinguishable by ear, but the whole collection fits on a flash drive or older player.
WAV from Audacity to MP3 for release
Mixed a podcast or track in Audacity? Convert the exported WAV into MP3, picking a bitrate to match the platform: 192 for voice, 256-320 for music.
MP3 → WAV for editing
Get a lossless WAV out of an MP3 so you can keep editing it in a DAW without piling up generation loss from re-encodes.
FAQ
Which input formats are supported?
Anything modern browsers can decode via the Web Audio API: MP3, WAV, M4A (iPhone AAC), AAC, OGG Vorbis, FLAC, OPUS, WebM audio. If your browser can play it, this converter can read it.
Which output formats are supported?
In the current version — MP3 and WAV. MP3 uses lamejs at 128, 192, 256 or 320 kbps. WAV is 16-bit PCM, lossless, at the original sample rate (or the one you pick).
Is quality preserved?
When exporting to WAV — fully lossless: no sample is lost. When exporting to MP3 — it depends on the bitrate: 128 kbps is fine for voice, 192-256 kbps for most music, 320 kbps is the maximum and almost indistinguishable from the original by ear.
Where does the file get processed?
Fully locally, in your browser. Decoding is done via the Web Audio API, MP3 encoding via lamejs (also WASM in the browser), WAV is assembled byte-by-byte from PCM samples. No network requests with your audio — you can disconnect after the page loads to verify.
Can I convert in batch?
Yes. Drop several files at once — each is converted in turn with the same settings. When done, download them individually or all together as a ZIP archive.
Which MP3 bitrate should I choose?
128 kbps — compact, good for voice, audiobooks, single-voice podcasts. 192 kbps — a balanced default for most music. 256 kbps — high quality for audiophiles. 320 kbps — maximum, useful for archives or dense music (rock, electronic).
Why no OGG, M4A, FLAC output?
These formats need heavy WASM codecs (libvorbis, libopus, FAAC) that would add 5-15 MB to the page. In MVP we kept only MP3 and WAV — they cover 95% of conversion tasks. OGG/M4A output is planned for later versions.