Add your M4A file
Drop one or more .m4a files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
M4A to FLAC
Re-encoding .m4a audio as .flac changes how the sound is compressed and which players will accept it. Free, private, and validated — the file never leaves your browser.
Private for supported formats — processed in your browser
Runs on your deviceConvert supported files
Drop M4A files here
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.About converting MPEG-4 audio to FLAC audio
Re-encoding .m4a audio as .flac changes how the sound is compressed and which players will accept it. An .m4a file is an MPEG-4 container that holds only audio, most often AAC and occasionally Apple Lossless. Apple coined the .m4a extension so audio would not be confused with .mp4 video, and it remains the default for iTunes purchases, Apple Music downloads, and Voice Memos.
A .flac file contains audio compressed with the Free Lossless Audio Codec, which shrinks recordings without discarding a single sample. Decoded .flac output is bit-identical to the source, so the format has become the standard for music archiving and high-resolution downloads. For this route the practical draw is genuinely lossless while roughly halving storage and open specification with no royalties anywhere in the chain — balanced against still several times larger than a good lossy encode, which is worth knowing before you commit a large batch.
Why convert M4A to FLAC?
The practical trigger for this conversion is usually a mismatch: with .m4a, the extension hides whether the contents are lossy or lossless, muddying quality expectations. Switching to .flac buys you genuinely lossless while roughly halving storage, which is why it is the better fit for ripping CD collections for permanent archival. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
M4A vs FLAC at a glance
| Aspect | MPEG-4 audio (.m4a) | FLAC audio (.flac) |
|---|---|---|
| Format type | Lossy — discards detail it judges invisible to shrink files | Lossless — every pixel or sample is preserved exactly |
| How it stores data | an ISO base media container restricted to audio tracks, structurally a sibling of MP4 | linear prediction followed by Rice coding typically yields files 40 to 60 percent the size of raw PCM |
| Strongest at | managing music inside iTunes and Apple Music libraries | ripping CD collections for permanent archival |
| Weak spot | the extension hides whether the contents are lossy or lossless, muddying quality expectations | still several times larger than a good lossy encode |
| Metadata | iTunes-style metadata atoms: title, album, artwork, composer, BPM, and the iTunSMPB gapless-playback data | vorbis comments for tags plus a dedicated PICTURE block for cover art; cue sheets can be embedded for whole-disc rips |
Pick FLAC as the output
Select .flac in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if FLAC is selectable, the route is real and validated.
Convert on your device
Press Convert. The transcode runs on an FFmpeg engine compiled to WebAssembly, so the audio never leaves your device.
Verify and download
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid FLAC file. Outputs keep the original filename with the .flac extension.
M4A to FLAC questions, answered
Will converting M4A to FLAC lose quality?
No new loss is introduced — since m4a is lossy-oriented and flac is lossless-oriented, everything the .m4a file still contains is carried over exactly. What was already discarded by the original lossy encode cannot be recovered, though; converting to .flac does not "restore" quality.
Is it private to convert M4A files here?
Yes — the .m4a file is processed inside your browser tab and never uploaded. The transcode runs on an FFmpeg engine compiled to WebAssembly, so the audio never leaves your device. Close the tab and the file is gone from memory.
Where will the FLAC file work?
All major browsers decode .flac, Windows 10 and later plus Android play it natively, and virtually every dedicated audio player supports it. The persistent gap is Apple's Music ecosystem, where converting to ALAC delivers the same audio in a supported wrapper.
Will the FLAC file be bigger or smaller than my M4A?
Larger, sometimes much larger. A lossless .flac must store every pixel or sample the decoder produced, without the perceptual shortcuts .m4a used. Use this route for editing headroom, not for saving space.
What happens to the metadata in my M4A file?
This converter strips container metadata deliberately (the FFmpeg command runs with metadata mapping disabled) so exported files do not leak recording details. In the source, iTunes-style metadata atoms: title, album, artwork, composer, BPM, and the iTunSMPB gapless-playback data; none of it is transmitted anywhere because the file never leaves your browser.
Can I convert FLAC back to M4A?
Yes — the reverse route exists as a separate tool. Bear in mind that round-tripping .m4a → .flac → .m4a is not a perfect undo when any lossy step is involved; keep your original if fidelity matters.