Your files stay on your Mac.
Converting QuickTime MOV to Matroska MKV rewraps your video in an open, widely supported container that plays natively on Windows, Linux, and most media players without proprietary codecs. Convertessa lets you set quality and process whole folders in one pass. Everything runs on your Mac — no upload, no account required.
Drag one MOV file or an entire folder onto Convertessa. Batch mode queues every .mov it finds automatically.
Choose Matroska MKV from the output format list. Set quality to balance fidelity and file size.
Click Convert. Convertessa processes every file locally — original resolution is preserved and your 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.
Convertessa encodes the video into the Matroska container using the codec you select. Use the quality slider to control fidelity — higher quality means larger files.
Yes. All audio tracks present in the source MOV are carried into the MKV output.
Yes. Drop a folder onto Convertessa or run convertessa /path/to/folder --to mkv in the terminal. Every .mov file in the folder is queued and converted in one pass.