What is the difference between WAV and M4A?

WAV stores uncompressed PCM audio — the raw samples, with nothing discarded. Quality is perfect and files are large: roughly 10MB per stereo minute at CD quality. It is the standard working format for recording and editing. M4A is an MPEG-4 container carrying AAC audio. It is Apple's standard format for music and voice memos, and delivers noticeably better quality than MP3 at the same bitrate, especially below 160kbps.

Will I lose anything converting WAV to M4A?

Yes — M4A is lossy, so some detail is discarded permanently in exchange for a much smaller file. A WAV is uncompressed, so expect the file to shrink to roughly a tenth of its size. At sensible bitrates most people cannot hear the difference on ordinary playback equipment. Keep your WAV original as the master, because you cannot get back what the encoder throws away.

Anything to watch out for with M4A?

M4A is the container; AAC is the codec inside it. The same container with a .m4b extension is used for audiobooks with chapter markers. An .m4a file can also hold Apple Lossless (ALAC) rather than AAC, which is why file size varies wildly between two files with the same extension.

What bitrate should I use?

For music, 192kbps MP3 or 128kbps Opus is the point where most people stop hearing a difference from the source. For speech and podcasts you can go much lower — 96kbps MP3 or 64kbps Opus is transparent for voice. Going above 256kbps on a lossy codec mostly just makes the file bigger.

What should I know about starting from WAV?

WAV is raw PCM with no standard tagging scheme, so artist and album metadata is usually absent before the conversion even starts. More broadly: WAV stores uncompressed PCM samples — the raw digital representation of the waveform, with nothing thrown away. A stereo CD-quality minute is about 10MB.

When is M4A the right choice?

M4A suits: apple ecosystem playback; better quality than MP3 at the same file size; voice memos and recordings destined for a phone. It is the wrong choice when older hardware that predates AAC support.

Is there a file size limit?

No hard limit — the constraint is your browser's memory. Files under 50MB convert in a few seconds. Larger files work but take longer, and a browser tab typically has 250-500MB to play with, so very large batches are better split into smaller groups.

Does this work on mobile?

Yes. The drop zone falls back to your phone's file picker, and the conversion runs on-device exactly as it does on desktop. Large files are slower on a phone because there is less CPU and memory available, but nothing about the workflow changes.

Convert WAV to M4A (AAC)

Convert WAV audio to M4A in your browser. Free, in your browser, no upload.

Drop audio files to convert

WAV, MP3, M4A (AAC), AAC, OGG, Opus, FLAC

Files stay on your device. Open DevTools' Network tab to verify.

MP3/AAC/Opus and decoding compressed input use browser WebCodecs; available in modern browsers only.

Overview

Why convert WAV to M4A (AAC)

WAV stores raw samples with nothing discarded, which is why a stereo minute costs about 10MB — fine while you are recording and editing, impractical for sharing or storing. Converting to M4A trades detail you are unlikely to hear for a file a fraction of the size. WAV also has no standard tagging scheme, so artist and album metadata is usually absent to begin with.

Comparison

WAV vs M4A (AAC): what actually differs

WAV compared with M4A (AAC) across encoding, fidelity, file size and support.
Attribute	WAV	M4A (AAC)
Full name	Waveform Audio File Format	MPEG-4 Audio (AAC)
Encoding	Binary	Binary
Fidelity	Lossless — bit-for-bit original samples	Lossy — more efficient than MP3 at equivalent bitrates
Typical size	Very large — about 10MB per stereo minute at 44.1kHz/16-bit	Roughly 20-30% smaller than MP3 at perceptually equal quality
Support	Universal. Every operating system, editor and player reads WAV.	Every Apple device, Android, modern browsers, most car systems.

How to

How to convert WAV to M4A (AAC)

01
Drop your WAV file
Drag one or more WAV files onto the drop zone above, or click to browse. Files stay on your device — there is no upload step.
02
Convert to M4A
convert.now parses the WAV and writes it out as M4A in a Web Worker, so the page stays responsive even on large files. Nothing is sent anywhere.
03
Download the result
Download the M4A file, or a zip of all of them for a batch. Filenames are preserved, with the extension changed to .m4a.

Why here

Why convert.now

Private
Files stay in your browser. No upload step. Nothing for anyone to see.
Fast
No queue, no upload wait. Conversion starts the moment you drop a file.
Free
No ads. No file-count limit. No sign-up wall. Just the converter.

FAQ

WAV to M4A (AAC): common questions

No. The WAV to M4A conversion runs entirely in your browser. Files never leave your device, and there is no server involved in the conversion at all. Open DevTools' Network tab and run a conversion if you want to confirm it — you will see the page and its code load, and no request carrying your file.

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Last updated 27 August 2026

Why convert WAV to M4A (AAC)

WAV vs M4A (AAC): what actually differs

How to convert WAV to M4A (AAC)

Drop your WAV file

Convert to M4A

Download the result

Why convert.now

WAV to M4A (AAC): common questions

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