formatika

Convert WebM to AAC

We turn WebM into AAC right in your browser — the file never goes to a server.

What you will lose

Nothing important: the target format does everything the source does.

How they differ

WebMAAC
Losslessnono
Lossyyesyes
Multichannelyesyes
Tagsyesyes
Released20101997
AuthorGoogleMPEG

WebM

Good at

  • The browser’s own format: plays with no plugins at all
  • Free of patent fees, which is why sites reach for it
  • Noticeably lighter than older-style MP4 at the same quality

Awkward about

  • Household devices and editing software barely know it
  • On Apple hardware it plays only sometimes
  • Audio is lossy only: Vorbis or Opus

Use it when

  • The video goes on a web page and is watched in a browser
  • You want the smallest file with the picture still alive
  • A screen recording or a short clip for a page

AAC

Good at

  • Noticeably better than MP3 at the same size
  • The native format for Apple gear and most phones
  • Handles multichannel audio and tags

Awkward about

  • Older devices and car stereos may refuse it
  • Lossy — the original cannot be recovered from it
  • Encumbered by patents, unlike Opus

Use it when

  • Listening on a phone without wasting quality
  • A voice memo, or a track pulled out of a video
  • You want a balance between size and sound

Common questions

Does the file get uploaded to a server?
Yes, this pair needs the server: browsers cannot encode that format. The file and the result are deleted within a couple of hours and never shared.
Will surround sound survive?
Yes, AAC carries more than two channels — 5.1 stays 5.1.
Can I get the original quality back afterwards?
No. AAC is lossy, and the discarded detail cannot be recovered. Keep the original if you may still need it.
How many files, and how large?
Up to 5 files at a time, 500 MB each. No sign-up, no watermarks.

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