Is this M4A to FLAC converter really free?

Yes. Up to 5 files at a time, no signup, no catch. The free tier adds a small watermark to image output — Pro ($9.99/mo or $49/yr) removes it, raises the file size limit to 500 MB, and unlocks unlimited batch conversion.

Are my files uploaded to a server?

No — and you can verify it yourself. Open DevTools → Network tab, then convert a file. You'll see zero upload requests. Everything runs right in your browser. We never see your files.

How long does conversion take?

Usually 1–3 seconds for a typical file. The very first conversion on a fresh page load may take 5–20 seconds while the converter engine loads — after that it's instant. Your CPU does all the work locally.

What is the file size limit?

Free: up to 10 MB per file, 5 files per batch. Pro: up to 500 MB per file, unlimited batch. If you're working with large videos or RAW photos, Pro is built for that.

Can I batch convert multiple M4A files at once?

Yes — drop multiple files at once (or Ctrl/Cmd+click to select them) and they all convert in parallel. Free accounts handle up to 5 files per batch; Pro has no limit.

What bitrate will the converted audio use?

We default to 192 kbps for MP3, 128 kbps for OGG/Opus, and 320 kbps for M4A/AAC. These settings are perceptually transparent — most listeners can't tell the difference in a blind test.

Will my metadata (ID3 tags, album art) be preserved?

Yes, when both formats support it. Tags carry over on conversions like MP3→M4A or FLAC→MP3. WAV has limited tag support, so some metadata may not transfer.

Will converting M4A to FLAC make the audio lossless?

No — FLAC is a lossless codec, but if the source M4A used AAC compression, that lossy encoding is already baked in. The FLAC wraps the decoded audio without further loss, but cannot undo the original AAC compression.

Why would I convert M4A to FLAC if it's not truly lossless?

For compatibility: FLAC is accepted by hi-fi DACs, audiophile music players (Audirvana, Roon, foobar2000), and NAS music servers that don't support M4A. The format change enables playback on hardware that doesn't read M4A.

How private is this converter?

Completely private — by design, not policy. There is no upload endpoint. Files are processed right inside your browser tab and disappear the moment you close it. We collect only anonymous page-view counts; your file content is never seen or stored.

M4A to FLAC Converter — Free, Online, No Upload

How to convert M4A to FLAC online

1
Drop your M4A file
Drag and drop your MPEG-4 Audio file onto the converter, or click to browse your files. You can select up to 5 at once. Nothing leaves your device — conversion happens right here in the browser.
2
Hit Convert — it happens locally
Click Convert and watch it go. There's no upload, no server queue, no waiting. The converter runs MPEG-4 Audio → Free Lossless Audio Codec entirely in your browser tab. Most files finish in 1–3 seconds.
3
Download your FLAC
Your Free Lossless Audio Codec file is ready. Click Download, or grab a ZIP if you converted a batch. Close the tab and everything disappears — no copies kept anywhere.

M4A vs FLAC: format overview

M4A

MPEG-4 Audio

Apple / MPEG Group · 2001

Compression: lossy
Transparency: No

✓ Better quality than MP3 at same bitrate (AAC codec)
✓ Native Apple ecosystem support
✗ Not universally supported on all Windows/Linux players

FLAC

Free Lossless Audio Codec

Josh Coalson / Xiph.Org · 2001

Compression: lossless
Transparency: No

✓ Lossless compression — identical to source
✓ 50–60% smaller than WAV with no quality loss

M4A magic bytes: 00 00 00 xx 66 74 79 70 4D 34 41

FLAC magic bytes: 66 4C 61 43

Why convert M4A to FLAC?

M4A (AAC audio in an MPEG-4 container) is excellent for everyday listening on Apple devices, but it hits a wall with audiophile hardware. Many high-end DACs, network streamers (Naim, Bluesound, Cambridge Audio), and music servers like Roon and JRiver Media Center have limited codec support — they read FLAC and WAV natively but often won't touch M4A or AAC. If you've built a hi-fi listening setup around any of this hardware, your iTunes purchases and GarageBand exports simply won't play.

Converting M4A to FLAC moves those files into a format the hardware understands. FLAC is the lingua franca of audiophile audio playback. Roon, Audirvana, foobar2000, and essentially every hi-fi media server treats FLAC as its primary input format. The conversion also improves metadata reliability — FLAC's Vorbis comment tags are handled more consistently across audiophile software than M4A's MP4 metadata atoms.

It's important to be honest about what the conversion doesn't do: because M4A uses lossy AAC compression, the FLAC output will not be "true lossless" audio. The FLAC container stores the decoded AAC audio without any further degradation, but the quality ceiling is set by the original M4A encode. Converting M4A to FLAC gives you compatibility with lossless-only hardware, not a quality upgrade over the source file.

Quality & file size: M4A to FLAC

Typical file sizes: M4A 3–6 MB → FLAC 20–40 MB.

Converting from lossy M4A to lossless FLAC will not recover detail the M4A codec already discarded — but the output will not degrade any further. This is useful when you need a lossless format for editing or compatibility without additional compression artifacts.

Color depth: M4A supports standard color, FLAC supports standard color.

Transparency: M4A does not support transparency. FLAC does not support transparency — transparent areas become solid white.

Frequently asked questions

Privacy: how FormatDrop handles your files

Your M4Afiles are converted 100% inside your browser. They are never uploaded to our servers, never stored, and never seen by anyone other than you. This isn't a privacy policy claim — it's an architectural guarantee: our server has no endpoint that receives file bytes.