Your files stay on your Mac.
Convertessa reads each .ogg file, decodes the Vorbis stream, and re-encodes it using the Opus codec. The output is saved as an .opus file inside an Ogg transport container. Set quality before you convert — everything runs locally on your Mac, with no upload.
Drag one .ogg file or an entire folder into Convertessa. Every file in the folder is queued for batch conversion automatically.
Choose Opus from the output list, then move the quality slider to balance file size against fidelity. Higher quality preserves more of the original audio.
Click Convert. Convertessa writes .opus files alongside the originals. No server, no upload — processing stays on your Mac.
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.
Yes. Ogg Vorbis is already a lossy format, and Opus is lossy too. Transcoding between two lossy codecs introduces generation loss. Set quality as high as your file-size budget allows to minimise it.
Output files use the .opus extension. Opus audio is carried inside an Ogg transport stream, so most modern players recognise it alongside standard .ogg files.
Yes. Convertessa removes embedded metadata from audio files during conversion, so the .opus output contains no residual tags from the source Ogg Vorbis file.