Your files stay on your Mac.
Matroska (.mka) is a flexible container that wraps audio encoded in many formats. Convertessa extracts the audio track and re-encodes it as WavPack, a lossless format that reduces file size without discarding a single sample. The entire process runs locally on your Mac — no upload, no internet required.
Drag one .mka file or an entire folder into Convertessa. Batch mode processes every Matroska file in one pass.
Choose WavPack from the output list. Convertessa encodes each audio track to lossless .wv, preserving every sample exactly as it was recorded.
Click Convert. Your .wv files appear alongside the originals — no upload, no cloud, everything stays on 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. WavPack stores every audio sample without alteration, so the decoded output is bit-for-bit identical to the original PCM stream inside the .mka container.
Yes. Drag the folder into Convertessa or run convertessa ./folder --to wv in Terminal to batch-convert every Matroska file in one pass.
Never. Convertessa runs entirely offline — your audio files are processed locally and never uploaded anywhere.