Crop and trim audio, paste in or join files, or just rapidly split one long file into many. Fission is streamlined for fast editing. Plus, it works without the quality loss caused by other editors, so you can get perfect quality audio even when editing MP3 and AAC files.

If you need to convert formats, Fission can do that too, with simple export or batch conversion to the MP3, AAC, Apple Lossless, FLAC, AIFF, and WAV formats.

Don't forget ringtones! Use Fission to make great custom ringtones for all your contacts.

Fission makes audio editing fast and easy - get it now!

What’s New

Version 2.5.0

New in Fission 2.5:

* Fission now has full compatibility with MacOS 10.15 (Catalina).

* Fission now offers full Dark Mode support, with a “Match System” option that uses the Dark theme when your Mac is in Dark Mode, and the Light theme when in Light Mode. You can also still select your desired theme manually, right in Fission's Preferences window.

* Several major improvements have been made to Fission's waveform drawing. In addition, the Dark theme once again correctly draws and highlights the waveform, restoring full functionality.

* A new wizard has been added to Fission, which includes a new “Quick Tour” to provide a helpful overview of the application, as well as update notes on the first launch of a new version.

Ratings and Reviews

4.0 out of 5
4 Ratings

4 Ratings

soundsation100 ,

Exclusive and Lossless Editing with Excellent Technical Support

Fission’s ability to edit and save sound documents with lossless results makes this application one of a kind. Even my technical issue was solved the same day I reported it. I’m pleased with this application, my purchase, and the software development team behind it. I hope they continue to grow this useful application.

wrldwzrd89 ,

Amazingly useful app

There have been countless times I have wanted to trim an MP3 or AAC file losslessly. This app does it right every time!

Flipped ,

Audio Swiss Army knife

I bought Fission for a large project where I had several 90 minute vocal recordings that I needed to cut out the empty audio spaces between each talking section while maintaining the same audio quality and not recompressing when saving. It worked simply and brilliantly for this. It took about 5-10 minutes to figure out. After using it for that simple project I've found myself using more of it's features for other things like breaking apart live musical recordings for iTunes and other little things that come up that I would have previously had to go through hoops to do. It's simple, quick and efficient. It's not a full featured audio editing suite - and that's what I love about it. I can do 90% of the things I need to do with audio files with Fissions' feature set. If you need to do simple audio editing, or clean up recordings and tags for iTunes you can't beat this software.

I would only ask that the developers consider making a version of Fission for video files. That would be a killer app.


Rogue Amoeba Software, LLC
10.8 MB

macOS 10.12 or later, 64-bit processor



Age Rating


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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