Your files stay on your Mac.
An ISO file contains the exact byte-for-byte contents of an optical disc. Converting it to ZIP extracts every file and folder from the image and repackages them into a standard archive you can open anywhere without disc-mounting software. Convertessa does the whole thing on your Mac — nothing is uploaded.
Drag one ISO file or an entire folder of disc images onto Convertessa. The app reads each image in sequence, ready to extract its contents.
Pick ZIP from the output format list. Convertessa extracts the full directory tree from each ISO and packs it into a matching ZIP archive.
Click Convert. Each ISO becomes a ZIP file beside the original, with the internal folder structure intact. Everything runs offline — 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.
Yes. Convertessa extracts the complete directory tree from the disc image and recreates it inside the ZIP archive, so every subfolder and file appears exactly where it was on the original disc.
No. Once converted, the ZIP is a standard archive any file manager or unzip tool can open. You no longer need virtual drive software or optical disc emulators to access the contents.
Yes. Drop a folder onto Convertessa or run convertessa /path/to/isos --to zip to batch-convert every ISO in that directory. Each disc image produces its own ZIP file.