Your files stay on your Mac.
Convertessa decodes your AAC audio and re-encodes it as Ogg Vorbis — an open, royalty-free format supported by VLC, Firefox, and most Linux audio stacks. Drop a file, pick your quality target, and the conversion runs entirely on your Mac; nothing is uploaded anywhere. Batch-convert a whole folder of tracks in a single pass.
Drag one AAC file or an entire folder onto Convertessa. The app queues everything automatically — albums, playlists, or individual tracks.
Choose Ogg Vorbis from the output format list. Because Ogg Vorbis is a lossy format, you can also set quality — slide the quality control to balance file size against audio fidelity.
Hit Convert. Convertessa processes every file locally and saves the Ogg Vorbis output next to your originals. No account, no upload, no waiting on a server.
Images, audio, video, documents, archives and eBooks — all converted natively, right on your Mac.
Pick a format you have — see everything Convertessa can turn it into.
Convert hundreds of files at once with per-type group defaults and individual overrides.
First-class support for HEIC, AVIF and WebP — encode and decode, both ways. Read JPEG XL and a dozen more modern formats too.
Drop files anywhere on the window. Native, instant, and exactly what you’d expect on a Mac.
Dial in compression, resolution and bitrate. Keep originals pristine or shrink for sharing.
Never overwrite a file by accident. Convertessa appends safe suffixes automatically.
Every job is logged locally. Re-run a previous conversion or revisit recent outputs in a click.
Bundle your converted files straight into a single ZIP, TAR or 7z — packaged and ready to share the moment a job finishes.
Right-click any file in Finder and choose Convert. A Quick Action handles it on the spot — no need to open the app first.
Shrink Convertessa to a tidy mini window that tucks into a corner — just a drop zone and a format picker for quick, one-off conversions.
No cloud. No account. No upload. Every conversion happens entirely on-device, using the power already in your Mac. What you convert is nobody’s business but yours.
Script conversions, wire them into your build, or batch a folder from the terminal. The same engine, no GUI required.
Read the full CLI documentation →Shrink Convertessa down to a small, focused window — drop, convert, done, with your recent conversions one click away.
macOS 14+ · Apple Silicon & Intel
New formats, new features, and fixes — every release, on the record.
Both AAC and Ogg Vorbis are lossy formats, so re-encoding introduces a small amount of generation loss. Set quality as high as your target file size allows to minimise the impact. For archival purposes, keep the original AAC alongside the converted file.
Yes. Drop a folder — or multiple folders — onto Convertessa and it queues every AAC file inside. All tracks are converted in one pass without manual intervention. You can also use the CLI: convertessa ./music-library --to ogg.
No. Convertessa runs entirely offline on your Mac. Your AAC files are decoded and re-encoded locally; they never leave your machine.