Your files stay on your Mac.
AVI (Audio Video Interleave) is a Microsoft container format that bundles audio and video streams into a single file. Convertessa reads your .avi files directly on your Mac and re-encodes them into 23 output formats — video containers, audio-only formats, and animated GIF — without sending anything to a server. Because the output uses lossy encoding, you can set quality before converting to balance file size and fidelity.
Drag a single .avi file or an entire folder into Convertessa. Batch mode processes every AVI in the folder in one pass — no size limit.
Pick the output format from the list — MP4, MKV, MOV, WebM, MP3, AAC, WAV, FLAC, or any of the 23 supported targets. Set quality if you want to control the lossy trade-off.
Click Convert. Convertessa processes everything locally on your Mac, preserves resolution, and strips metadata from the output file. No upload, no account required.
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 runs entirely offline. Your .avi files are processed on your Mac and never leave your machine.
Yes. Drop a folder onto Convertessa — or run convertessa /path/to/folder/ --to mp4 in the terminal — and it converts every AVI inside in a single batch.
Yes. Choose an audio-only output format such as MP3, AAC, WAV, FLAC, or OPUS from the list and Convertessa extracts the audio track from your AVI file.