Your files stay on your Mac.
WAV stores uncompressed PCM audio — accurate but large. Converting to AAC applies lossy compression that shrinks file size while keeping the audio sounding close to the original. Convertessa runs the whole process locally on your Mac; your files never touch a server.
Drag one WAV file or an entire folder onto Convertessa. Batch conversion processes every file in a single pass.
Choose AAC from the output format list, then set quality to dial in the trade-off between file size and audio fidelity.
Click Convert. Convertessa writes AAC files next to your originals — no upload, no account, no internet required.
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. Drop a folder onto Convertessa or run convertessa ./folder --to aac from the terminal. Every WAV file inside is converted in one pass.
Yes. Because AAC is a lossy format, Convertessa lets you set quality before converting. Higher quality keeps more detail and produces larger files; lower quality produces smaller ones.
No. Convertessa converts files locally on your Mac. Your audio never leaves your device.