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Free · No upload · MP3, WAV, OGG, M4A, FLAC

Audio Converter

Convert audio between MP3, WAV, OGG, M4A and FLAC — re-encoded in your browser, never uploaded.

100% freeNo upload capsNo watermarkNo sign-up
  1. 1Pick file
  2. 2Configure
  3. 3Download
Converting to MP3 is the universal choice — every device and app plays it. WAV is uncompressed (large, for editing), FLAC is lossless at about half the size, and converting MP3 → MP3 at a lower bitrateis how you shrink a file that's too big to send.
  • Files never leave your browser — processed entirely on your device
  • No upload, no queue, no waiting for a worker to free up
  • No upload caps — capacity scales with your device's RAM (up to ~2 GB per file on desktop)

About Audio Converter

Every other audio converter uploads your file to a server, queues it behind a free-tier limit, and emails you a link. This one runs the same FFmpeg codecs those servers use — compiled to WebAssembly, running in your browser tab. Your recording never leaves your device, there is nothing to wait in line for, and there is no daily quota.

Five output formats cover the real-world cases: MP3 for universal playback, WAV when an editor or DAW wants uncompressed PCM, FLAC for lossless archiving at roughly half the WAV size, OGG Vorbis for open-source pipelines, and M4A/AAC for Apple devices. Lossy formats get a bitrate ladder from 64 to 320 kbps plus a VBR mode that spends bits where the audio is complex.

It also handles the conversion nobody advertises: MP3 to MP3. Re-encoding a 320 kbps file at 128 kbps, or stereo to mono, is how you shrink a voice recording that is too big to send — same tool, same privacy.

How it works

  1. Drop your audio fileAccepts MP3, WAV, M4A, OGG, FLAC, AAC, OPUS. Multi-hour recordings work — processing happens locally, so there is no upload cap to hit.
  2. Pick the output formatMP3 for compatibility, WAV for editing, FLAC for lossless archiving, OGG or M4A for specific ecosystems. For lossy formats, choose a bitrate (192 kbps is the everyday sweet spot) or VBR for the best quality per megabyte.
  3. Optionally remix channelsKeep the source layout, or force mono / stereo. Mono halves the size of voice recordings with no audible cost — podcasts, lectures, voice memos.
  4. Click Convert audioThe encoder runs in your browser. A typical song converts in seconds; an hour-long recording takes a couple of minutes depending on your device.

When to use Audio Converter

Converting a WAV bounce to MP3 for sharing
A 40MB WAV from your DAW becomes a 4MB MP3 at 192 kbps — small enough to message, indistinguishable for casual listening.
Shrinking a voice recording that is too big to send
A 320 kbps stereo voice memo re-encoded at 96 kbps mono is roughly a seventh of the size and sounds the same for speech. This is the MP3-to-MP3 case most converters hide.
Archiving CDs or masters losslessly
FLAC stores the exact original samples at about half the WAV size. Convert WAV masters to FLAC for storage; convert back to WAV any time with zero loss.
Making OGG/OPUS files play on older devices
Voice messages exported from chat apps often arrive as OGG or OPUS, which older car stereos and MP3 players refuse. Convert to MP3 once and it plays everywhere.
Feeding an audiobook app that wants M4A
Apple Books and many audiobook apps prefer M4A/AAC. Convert MP3 chapters to M4A without touching iTunes.

Frequently asked questions

How do I convert audio to MP3 online for free?
Drop your file into AntiUpload Audio Converter, pick MP3 and a bitrate, click Convert. No upload, no watermark, no sign-up, no daily quota — the conversion runs in your browser with FFmpeg compiled to WebAssembly.
Does converting MP3 to MP3 at a lower bitrate reduce quality?
Slightly — every lossy re-encode adds a small generational loss on top of the bitrate change. For speech it is inaudible even at 96 kbps. For music, stay at 192 kbps or above, or use VBR. If you need to re-encode many times, work in FLAC or WAV between steps.
Which format should I pick?
MP3 if it has to play everywhere. WAV if an editor or DAW is the next stop. FLAC to archive losslessly at half the WAV size. M4A for Apple ecosystems. OGG for open-source toolchains. When in doubt: MP3 at 192 kbps.
Is there a file-size or length limit?
No upload caps and no daily quota — processing is local, so the practical limit is your device's memory. Multi-hour recordings convert fine on a typical laptop; very long files just take proportionally longer.
Is my audio uploaded anywhere?
No. The file is read into your browser's memory, converted there, and the result is saved straight back to your device. Disconnect from the internet after the page loads and the conversion still works.
Can I convert video files to audio here?
Use our Extract Audio tool for that — it pulls the audio track out of MP4 / MOV / WebM into the same five formats, and stream-copies losslessly when the codec already matches.

Related tools

Extract AudioPull the audio track out of any video — choose MP3, WAV, OGG, M4A, or FLAC. Quality presets, mono/stereo, optional VBR for lossy formatsAudio TrimmerCut a clip out of an MP3, WAV, M4A, OGG, FLAC, AAC, or OPUS — fast and lossless, no re-encodeAudio JoinerCombine two or more audio files into one — pick MP3, WAV, M4A, OGG, or FLAC output, with optional crossfades or silence gaps between clipsChange Audio VolumeMake an audio file louder or quieter — multipliers from 0.25× to 3×, output to MP3 / WAV / M4A / OGG / FLAC