Your files stay on your Mac.
Convertessa reads the audio track from your iTunes M4V file and writes it as Dolby Digital AC-3. The video stream is dropped; the output is a standalone .ac3 audio file. Everything runs on your Mac — your files never leave the machine.
Drag one M4V file or an entire folder onto Convertessa. Batch mode processes every file in one pass with no extra steps.
Choose AC-3 from the output format list. Set quality to dial in the fidelity of the Dolby Digital stream before you convert.
Click Convert. Convertessa extracts and encodes the audio track entirely offline — no upload, no server, no waiting.
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 an audio-only format. Convertessa extracts the audio track from your M4V and writes a standalone .ac3 file — the video stream is not carried over.
Yes. Drop a folder onto Convertessa or use the CLI: convertessa *.m4v --to ac3. Every M4V in the folder is processed in a single pass.
Never. Convertessa runs entirely on your Mac. Conversion happens offline and your files never leave your machine.