BYTETOOLS

MP3 to FLAC Converter

Convert MP3 to FLAC online for free. Decode MP3 audio into a lossless FLAC file for archiving or editing, right in your browser — nothing is ever uploaded.

Drop an MP3 file here or click to browseYour audio is converted locally and never uploaded.

What is the MP3 to FLAC Converter?

The ByteTools MP3 to FLAC Converter decodes an MP3 file and stores the result as FLAC, a lossless format supported by most players, DAWs and hi-fi systems.

  • Lossless FLAC output — no further quality loss ever
  • Ideal for editing without stacking lossy re-encodes
  • 100% local conversion — audio is never uploaded
  • Works with any MP3 bitrate or sample rate
  • Built-in preview player before download
  • Free, unlimited and works offline once loaded

How to use the MP3 to FLAC Converter

  1. 1

    Drop an MP3 file onto the box or click to browse for one.

  2. 2

    Click Convert to FLAC and wait for the in-browser engine to finish.

  3. 3

    Preview the decoded audio with the built-in player.

  4. 4

    Download your new FLAC file.

About the MP3 to FLAC Converter

The ByteTools MP3 to FLAC Converter decodes an MP3 file and stores the result as FLAC, a lossless format supported by most players, DAWs and hi-fi systems. Drop in an MP3 and download a FLAC copy in seconds.

One thing an honest converter must say up front: FLAC cannot restore detail the MP3 encoder already threw away. The output preserves the MP3's current sound exactly, with no further loss — useful when a workflow only accepts FLAC, or when you want to edit or archive without stacking additional lossy re-encodes on top.

Everything runs 100% locally in your browser via a WebAssembly build of ffmpeg. Your audio never leaves your device — no uploads, no server, no account — and the tool keeps working offline once loaded.

Frequently asked questions

Does converting MP3 to FLAC improve quality?

No. MP3 is lossy, and the detail removed during MP3 encoding is gone permanently. Converting to FLAC gives you a bit-exact lossless copy of what the MP3 currently sounds like, but it cannot recreate the original recording.

Why convert MP3 to FLAC at all?

FLAC is the right container for editing and archiving: you can process, tag and re-save it repeatedly with zero additional loss. Some audio software and hardware also simply require FLAC or another lossless input.

Why is the FLAC file bigger than my MP3?

FLAC stores the fully decoded audio losslessly, which takes far more space than MP3's compressed representation — typically five to ten times more. The size increase is expected and does not indicate added quality.

Is my audio uploaded to a server?

No. The conversion runs entirely in your browser using WebAssembly. Your MP3 is processed on your own device and never sent anywhere.

Will the FLAC play on my devices?

FLAC is supported natively by Windows, Android, macOS and iOS (11+), most media players and virtually all audio editors. If a device refuses it, converting to WAV with our FLAC to WAV tool is a universal fallback.

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