Compress MP3 to Opus

MP3 files are already compressed, but Opus can compress further at a different bitrate. The size reduction is significant for sharing, uploading, and storage.

For email attachments, 128-192kbps works well. For music sharing, use 256-320kbps. AudioUtils lets you drop your file and convert instantly. No upload to a server, no waiting.

Sizes are comparable: MP3 and Opus both sit near 1.4–0.5 MB per stereo minute, so this conversion is about compatibility, not storage. You're stacking a second lossy generation. At a generous bitrate that's inaudible, but if you still have a lossless original, encode from that instead: one generation always beats two.

Most people meet MP3 through downloads. It is a fine format there; the trouble is that MP3 is lossy and built for playback, so editing, production, and some apps and engines want a different format. Opus is the destination because it plays essentially everywhere — Discord recordings and every ordinary phone, browser, and player. Disk usage barely moves — this conversion buys compatibility rather than space. Both MP3 and Opus are lossy, so this pair stacks a second encode — at a generous bitrate it stays inaudible, but if a lossless original of the MP3 exists, encode the Opus from that instead.