Your files stay on your Mac.
Convertessa decodes your Ogg Vorbis files and re-encodes them as Apple M4A (.m4a), an AAC-based format natively supported by iOS, macOS, and iTunes. You control output quality before encoding starts. Everything runs locally on your Mac — no files are uploaded anywhere.
Drag one or more .ogg files — or an entire folder — into Convertessa. Batch conversion is supported natively; mix as many files as you need.
Choose Apple M4A from the output format list. Set quality to control the fidelity of the encoded AAC audio before conversion begins.
Click Convert. Convertessa encodes your files to .m4a on your Mac. Nothing is sent to any 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.
Yes. M4A uses AAC, a lossy codec, so Convertessa lets you set the output quality before encoding. Higher quality produces larger files; lower quality produces smaller files with more compression.
Yes. Drop a folder onto Convertessa or run convertessa /path/to/folder --to m4a in the terminal. Every .ogg file in the folder is converted in one pass.
No. Convertessa runs entirely on your Mac. Your .ogg files are decoded and re-encoded locally — nothing is sent to any server.