Your files stay on your Mac.
AC-3 is a lossy compressed audio format used in DVDs, Blu-rays, and broadcast streams. Converting to AIFF decodes the compressed bitstream into a full uncompressed audio file. The result is a Mac-native AIFF ready to open in any audio editor or DAW without re-encoding.
Drag one .ac3 file or an entire folder into Convertessa. Batch mode handles as many files as you need in a single pass.
Choose AIFF from the output format list. Convertessa preserves the original sample rate and bit depth from the AC-3 stream.
Click Convert. Convertessa decodes each file locally on your Mac — nothing is uploaded anywhere.
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. AC-3 is a lossy format — some audio information is discarded at encode time and cannot be recovered. Converting to AIFF produces an exact uncompressed decode of the AC-3 stream with no further loss, but the quality ceiling is fixed by the original AC-3 encode.
Yes. Drop an entire folder onto Convertessa or point the CLI at a directory: convertessa /path/to/folder --to aiff. Every .ac3 file in the folder is converted in one batch.
AIFF is the native uncompressed format for Apple tools — Final Cut Pro, Logic Pro, and GarageBand open it without conversion. If you need broad cross-platform compatibility, WAV is an equally lossless alternative; choose whichever format your downstream tool expects.