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, eBooks and fonts — 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.