Audio Converter

Turn MP3, M4A, OGG or FLAC into WAV, FLAC or Opus.

Change an Audio File’s Format Without Uploading It

Drop in one file or a whole folder of them — MP3, M4A from an iPhone, AAC, OGG, Opus, FLAC or WAV — and choose what you need back. WAV is the universal editing format, FLAC halves the size with no loss at all, and Opus gives small files that still sound excellent. Sample rate and channel count can be changed on the way, for example 48 kHz for video or 16 kHz mono for speech recognition.

Your browser decodes each file, and the encoders run on this page: FLAC is written by a lossless encoder built into the tool, and Opus uses the browser’s own encoder where one exists. There is one honest gap: no browser includes an MP3 encoder, so this tool does not produce MP3 rather than sending your audio to a server to do it.

Key features

  • Reads almost anything your browser can play: MP3, M4A, AAC, OGG, Opus, FLAC, WAV and WebM audio.
  • Lossless FLAC at 16 or 24 bits, typically 40–60% smaller than WAV.
  • WAV in three depths — 16-bit, 24-bit or 32-bit float.
  • Opus in an Ogg file at 64–192 kbps where the browser has an Opus encoder.
  • Batch conversion of up to 50 files, returned together as one ZIP.
Files processed locally in your browser

This tool does its work inside your browser using native Web APIs. The files and text you give it are processed on your device and are not uploaded to our servers.

How to use: Audio Converter

  1. Add your files
    Drop one or more audio files onto the box, or tap it to choose them.
  2. Choose the format
    Pick WAV, FLAC or Opus, and optionally a new sample rate or mono.
  3. Convert
    Press Convert and download. One file downloads directly; several arrive as a ZIP.
  4. Check the result
    Each file keeps its name with the new extension, so it slots straight back into your folder.

Technical specifications

Processing locationEntirely in your browser — no server round trip
Data uploadedNone. Files and text never leave your device
PriceFree — no account, no trial, no usage cap
CategoryAudio
Works offlineYes, once the page has loaded
Browser supportChrome 90+, Edge 90+, Firefox 90+, Safari 15+
Interface languagesEnglish, 中文, हिन्दी, Español, العربية

Frequently asked questions

Can it convert to MP3?

No. Browsers ship MP3 decoders but no MP3 encoder, so making an MP3 would mean uploading your file to a server. For small files choose Opus, which sounds better than MP3 at the same size; for editing choose WAV or FLAC.

Is FLAC really lossless?

Yes. Every sample decodes back to exactly what was encoded. Converting a lossy MP3 to FLAC keeps the MP3’s quality exactly — it does not add back anything the MP3 threw away.

Why did an M4A or ALAC file fail?

Decoding is done by your browser. Chrome, Edge, Firefox and Safari all read AAC M4A files; Apple Lossless (ALAC) is read by Safari and some others. If one browser refuses a file, try another.

What sample rate should I pick?

Keep the original unless a program asks for something specific: 48 kHz is standard for video, 44.1 kHz for music CDs, and 16 kHz mono is plenty for voice transcription.

Are my files uploaded?

No. Decoding and encoding both happen in this tab, so the files never leave your device and conversion works offline once the page has loaded.

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