FLAC to M4A Converter

What happens when you convert FLAC to M4A

• The audio is decoded and written as AAC at 192 kbps in an M4A container.
• FLAC is lossless and M4A is not, so this is where size is saved: expect the M4A to be roughly one fifth of the size.

How to convert FLAC to M4A online

1. Press "Choose FLAC files" and select one or more files, or drag them onto the box. You can add files of any size your device can hold in memory.
2. Adjust the settings if you need to: the bitrate controls quality and size. The defaults suit most people.
3. Press "Convert to M4A". The first audio or video conversion downloads the converter engine, about 32 MB, which your browser then keeps for next time.
4. Save each M4A with its download button. Close the tab and every trace of the files is gone from memory.

Why convert FLAC to M4A?

FLAC files usually come from CD rips, hi-res music stores and audio archives. People convert them to M4A because M4A is the native audio format of the iPhone, iTunes and Apple Music.

In short, FLAC is good at what it was made for, and M4A is the more practical choice when the file has to play on another device or app. FLAC plays in current browsers and most Android devices; iPhones play it in the Files app, while M4A plays in all current browsers and every Apple device.

How to convert FLAC to M4A on Windows, Mac, iPhone and Android

On Windows

Open this page in Chrome, Edge or Firefox, drag your FLAC files in from File Explorer, and press Convert. Each M4A is saved to your Downloads folder. If you prefer a desktop program, VLC can also convert FLAC to M4A: choose Media, then Convert / Save.

On a Mac

Safari, Chrome and Firefox all work. Drag the FLAC files from Finder onto the drop zone and the M4A files land in Downloads.

On iPhone and iPad

Open the page in Safari and tap Choose FLAC files. You can pick from Photos or from the Files app. The converted M4A appears in Files, in the Downloads folder.

On Android

Open the page in Chrome, tap Choose FLAC files and pick them from Files or your gallery. The M4A is saved to the Download folder, where any file manager can find it. Keep the screen on while a long video converts, because Android may pause a tab in the background.

Best settings for FLAC to M4A

M4A is a lossy format, so the bitrate decides both the sound quality and the file size. Size grows in a straight line with bitrate: double the bitrate and the file doubles.

Because the FLAC is lossless, any bitrate you choose starts from a perfect source. 192 kbps is a safe default; go to 256 or 320 kbps if the music has a lot of cymbals, applause or reverb.

FLAC vs M4A: the differences

About FLAC and M4A files

What is a FLAC file?

FLAC shrinks audio to about half to two thirds of WAV size without losing a single sample, so it can be decoded back to a bit-identical copy of the original.

What is an M4A file?

M4A is an MP4 file that only holds audio, which is why renaming one to .mp4 often works. Voice Memos on iPhone saves recordings as M4A.

FLAC to M4A not working? Common problems

• The conversion is slow. Audio and container changes take seconds, but re-encoding video runs on your own processor. Lower the resolution to 720p, close other tabs, and keep the device plugged in.
• The tab stops or reloads on a very large file. Browsers limit how much memory one tab can use, around 2 GB and less on phones. Split long recordings or convert them on a computer.
• Song titles are missing. Tags such as title and artist are copied when M4A can store them, but cover art is not carried over.

Convert FLAC to M4A with ffmpeg

This converter runs ffmpeg inside your browser. If you would rather use the ffmpeg command line on your own computer, this command produces an equivalent M4A with the same kind of settings:

ffmpeg -i input.flac -vn -c:a aac -b:a 192k output.m4a

Replace input.flac with the name of your file. For a whole folder of FLAC files, run the command in a loop, or drop them all on the converter above, which processes them one after another.