Your files stay on your Mac.
AU is a Unix-native audio format used in Java applications and legacy Unix systems. WAV stores raw PCM samples and is universally supported by audio editors, DAWs, and every major operating system. Converting AU to WAV makes your audio immediately usable anywhere without re-encoding or quality loss.
Drag one AU file or an entire folder onto Convertessa. Files never leave your Mac — no upload, no account required.
Pick WAV from the output format list. Convertessa preserves the original sample rate, bit depth, and channel layout exactly as found in the source file.
Click Convert. Each AU file is written out as a WAV alongside the original. Batch jobs across whole folders finish in seconds.
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.
No. Convertessa runs entirely on your Mac. Your audio files are never uploaded or sent to any server.
No. WAV stores uncompressed PCM audio, the same encoding most AU files use. The conversion is lossless — sample rate, bit depth, and channel count are preserved exactly.
Yes. Drop a folder onto Convertessa or run convertessa folder/ --to wav from the command line. Every AU file inside is converted in one pass.