Are my WebM files uploaded anywhere?

No. This conversion runs entirely inside your browser, so the file never leaves your device. You can confirm it yourself: open the network tab of your browser's developer tools and convert something. You will see the page load, plus the analytics and advertising the site is paid for with — and nothing carrying your file.

Is converting WebM to M4A free?

Yes. There is no account, no watermark and no limit on how many files you convert — it runs on your own machine, so it costs us nothing to let you. Files up to 100 MB are handled in the browser.

Does converting WebM to M4A lose quality?

M4A is a compressed format, so some data is discarded. At the default setting the difference is not visible; you can raise the quality setting if you need to be certain. Only the first soundtrack is kept. A film with a second language or a commentary track loses it.

Do I need to install anything to open M4A files?

No installation is needed for the conversion itself — it runs in the browser you already have. Opening the M4A afterwards needs whatever software normally handles MPEG-4 Audio on your device.

WebMtoM4A

Convert WebM to M4A

Up to 100 files at once. Mixed formats are fine.

You can convert WebM to M4A free and without an account: drop the file above and the M4A is ready to download in a second or two. The conversion happens inside your own browser, so the file is never uploaded — it works on Windows, Mac, Linux, iPhone and Android, and keeps working with the network switched off.

What WebM and M4A are for

The royalty-free web video format. Small files, plays in browsers, ignored by most TVs.

AAC audio in an MP4 container. What iTunes and voice memos produce.

How to convert WebM to M4A

Drop your WebM file onto this page, or click to pick one.
Choose M4A as the target. The conversion runs inside your browser — the file is never uploaded.
Download the finished M4A file.

WebM vs M4A: what changes

WebM compared with M4A
	WebM	M4A
Full name	WebM Video	MPEG-4 Audio
File extension	.webm	.m4a
Media type	video/webm	audio/mp4
Compression	Lossy — file size is bought with quality	Lossy — file size is bought with quality

Quality: Some quality is given up for a smaller file. At the default setting the difference is hard to see.
Where it runs: This conversion runs inside your browser. Your file is never uploaded, and it works with the network disconnected.
What can be lost: Only the first soundtrack is kept. A film with a second language or a commentary track loses it.

WebM to M4A: common questions

Are my WebM files uploaded anywhere?: No. This conversion runs entirely inside your browser, so the file never leaves your device. You can confirm it yourself: open the network tab of your browser's developer tools and convert something. You will see the page load, plus the analytics and advertising the site is paid for with — and nothing carrying your file.
Is converting WebM to M4A free?: Yes. There is no account, no watermark and no limit on how many files you convert — it runs on your own machine, so it costs us nothing to let you. Files up to 100 MB are handled in the browser.
Does converting WebM to M4A lose quality?: M4A is a compressed format, so some data is discarded. At the default setting the difference is not visible; you can raise the quality setting if you need to be certain. Only the first soundtrack is kept. A film with a second language or a commentary track loses it.
Do I need to install anything to open M4A files?: No installation is needed for the conversion itself — it runs in the browser you already have. Opening the M4A afterwards needs whatever software normally handles MPEG-4 Audio on your device.