Fission can crop and trim audio, paste in or join files, or just rapidly split one long file into many. It's 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! You can rapidly export or batch convert files to the MP3, AAC, Apple Lossless, FLAC, AIFF, and WAV formats.

Key Features:

• Edit MP3, AAC, Apple Lossless, and AIFF files with no quality loss
• Quickly split a long audio file into smaller files
• Remove unwanted content, such as commercials, from your audio file
• Re-arrange audio in a single file, copy audio from one file to another, or merge with a quick drag and drop
• Create great-sounding MP3 or AAC ringtones for your cell phone.

What's New:

Fission 2.9.0

• Initial Support for MacOS 26 (Tahoe)
  Fission now has initial support for MacOS 26 (Tahoe), and will no longer warn at launch when run on Tahoe. If you encounter any issues, please reach out via the “Contact Rogue Amoeba…” option in the “Help” menu.
• Lovely Interface Updates
  Fission’s user interface has been polished, with a refreshed light theme that leans into the app’s gold coloring, as well as new art assets throughout the app. Of particular note, there’s a new “Start” window, and the overview bar at the top of a file now more clearly shows the visible area when zoomed in.
• An Updated App Icon
  Fission’s app icon has been updated and modernized, in part to enable it to escape from the icon jail Apple implemented in MacOS 26 (Tahoe).
• The “Cut” and “Cut & Split” menu items now correctly copy audio when used.
• Improvements have been made to the “Set Playhead” command, making it more forgiving with entered data.
• Drawing issues which could be seen when highlighting fields in Fission’s Inspector have been corrected.
• The “i” and “o” keyboard shortcuts, used to mark the beginning and end of selections, now provide VoiceOver cues.
• Fission’s “Start” window behavior has been adjusted. It will now show at launch, whenever the last file window is closed, and when clicking Fission’s icon in the Dock.
• Fission’s menus have been reviewed and updated, with the following changes:
• The “Split at Playhead” option has moved to the “Tools” menu, from its previous home in the “Clip” menu.
• The “Show Inspector” option has moved to the “View” menu, from its previous home in the “Window” menu.
• The order of items in the “Window” menu has been refined.

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