Wrap MP3 audio in a lossless FLAC file for FLAC-only players and libraries. It runs privately in your browser — and tells you honestly what FLAC can and can’t do for an MP3.
The MP3 to FLAC converter turns MP3 audio (MPEG-1/2 Layer III) into FLAC (Free Lossless Audio Codec) directly in your browser. Some players, servers and libraries only accept FLAC, and FLAC is a stable container if you plan to edit or re-encode the audio later without adding another lossy generation.
MP3 is the most universally supported lossy format; plays on virtually every phone, car stereo, browser and editor. FLAC is lossless compression — typically 50–60% of the size of the equivalent WAV while decoding bit-identically. Because MP3 is already lossy, converting to FLAC keeps the audio exactly as it sounds now but cannot restore detail that was removed when the MP3 was made — expect a much larger file with the same quality. Honesty note: genuine FLAC is made from a lossless source. A FLAC made from an MP3 is lossless from that point on, but it can never recover what the MP3 discarded — which is why the Audio File Info Analyzer can often spot such files by their 16 kHz cutoff.
Your file is decoded to 32-bit floating-point samples by the browser’s own audio decoder — and at the file’s own sample rate, not a resampled one. You can optionally resample or switch channels. It is then encoded to FLAC on your device; for a lossy target the result is decoded again for the preview, so you hear what you will get. Typical size: about 5–6 MB per minute for CD-quality stereo.
Source format facts: MP3 files are lossy; usual bandwidth: typically low-passed at 16–20 kHz depending on bitrate. Target facts: FLAC is lossless; usual bandwidth: full bandwidth, exactly as recorded.
Import MP3s into a lossless-only workflow.
Edit and save without another lossy encode.
FLAC supports rich tags and cover art.
Some DJ, audio-server and DAW setups prefer FLAC.
| From | MP3 — MPEG-1/2 Layer III |
|---|---|
| To | FLAC — Free Lossless Audio Codec |
| Direction | lossy → lossless |
| Typical size | about 5–6 MB per minute for CD-quality stereo |
| Tags | MP3: ID3 → FLAC: Vorbis comments |
No. It only prevents any further loss. The sound is identical to the MP3.
For compatibility with FLAC-only players and to edit without stacking another lossy encode.
From the decoded MP3, yes — the FLAC decodes to exactly the same samples, verified by an MD5 stored in the file.
This tool runs entirely in your browser using the Web Audio API. Nothing is uploaded, stored or shared — there is no server to send your file to, so it works offline once the page has loaded.
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