Your files stay on your Mac.
Converting a WMV file to FLAC pulls the audio track out of the Windows Media container and saves it as a lossless FLAC file. The source video is never re-encoded — only the audio stream is extracted, so no audio data is discarded or degraded. Every file stays on your Mac; nothing is uploaded.
Drag one WMV file or an entire folder into Convertessa. Batch mode finds every .wmv file in the folder and queues them in a single pass.
Pick FLAC from the output format list. Convertessa will extract the audio stream and encode it to lossless FLAC — no quality compromise, no guessing.
Click Convert. Convertessa writes a .flac file alongside each source file. Nothing leaves your Mac at any point.
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. FLAC is a lossless format — every audio sample from the original WMV file is preserved exactly. The only things removed are the video track and the Windows Media container wrapper.
Never. Convertessa runs entirely on your Mac. Files are read and written locally; no data is sent to a server or cloud service.
Yes. Drop a folder onto Convertessa and it processes every .wmv file inside. From the command line: convertessa ./folder/ --to flac.