Your files stay on your Mac.
Converting iTunes M4V to Matroska pulls the audio track from an M4V file and rewraps it in an open MKA container. Convertessa runs entirely on your Mac—no upload, no server, no internet connection required. Drop a single file or a whole folder and set quality on every output.
Drag one M4V file or an entire folder into Convertessa. The app reads your files locally—nothing is uploaded at any point.
Choose Matroska from the output list, then set quality to balance file size against audio fidelity.
Click Convert. Convertessa extracts the audio track from each M4V and writes an MKA file alongside the originals.
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 converts entirely offline. Your files are read and written locally; no data is sent to any server.
Yes. Because Matroska MKA uses lossy encoding, Convertessa lets you set quality before converting. A higher setting preserves more detail; a lower one produces a smaller file.
Yes. Drop a folder onto Convertessa or pass a directory to the CLI (convertessa ./folder --to mka) to batch-convert every M4V inside.