Your files stay on your Mac.
Convertessa extracts the audio stream from your MPEG files and re-encodes it as Opus, a modern open codec built for efficient, high-fidelity audio. Everything runs locally on your Mac—no files are uploaded and no account is required. Convert a single clip or an entire folder in one pass.
Drag one or more MPEG files—or a whole folder—into Convertessa. Files stay on your Mac throughout.
Choose Opus from the output format list. Optionally set quality to control the fidelity of the encoded audio.
Click Convert. Convertessa processes each file locally and saves the Opus output alongside your originals.
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. Opus is an audio-only format, so Convertessa extracts the audio stream from your MPEG file and encodes it as Opus. The video track is not carried over.
Yes. Drop a folder onto Convertessa or run convertessa /path/to/folder --to opus from the command line. Every MPEG file inside is converted in a single pass.
No. All conversion runs locally on your Mac. Your files never leave your machine.