Your files stay on your Mac.
Convertessa pulls the audio track from your MP4 files and re-encodes it as TTA — a lossless format that reproduces every sample exactly. The original video stream is discarded; only the audio is written to the output file. Everything runs locally: no upload, no internet connection required.
Drag one MP4 or an entire folder onto Convertessa. The app reads the embedded audio track from each file and queues it for conversion.
Choose TTA from the output format list. Because TTA is lossless, no quality trade-off is involved — every sample from the source audio is preserved exactly.
Click Convert. Convertessa writes a .tta file for each input alongside your originals. Files never leave your Mac.
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. TTA is a lossless codec, so every audio sample from the MP4 is reproduced bit-for-bit in the output. No quality is discarded during conversion.
Convertessa extracts only the audio stream and encodes it as TTA. The video track is not included in the output file.
Yes. Drop a folder onto Convertessa and every MP4 inside is queued for batch conversion. You can also run convertessa /path/to/folder --to tta from the command line.