Your files stay on your Mac.
Convertessa reads each OPML outline and maps its structure into Jupyter Notebook cells, turning headings and nested outline items into markdown. The resulting .ipynb file opens directly in JupyterLab, VS Code, or any notebook viewer. Your files never leave your Mac — no upload, no account required.
Drag one .opml file or an entire folder into Convertessa. The app finds every OPML file in the selection, including files in nested subfolders.
Pick Jupyter Notebook from the output list. Set quality to control output fidelity, then confirm your selection.
Convertessa converts each OPML outline to a .ipynb file, strips metadata, and writes the results to your chosen folder. Open them straight away in JupyterLab or VS Code.
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 on your Mac. OPML files are read locally and the resulting .ipynb files are written to your output folder — nothing is sent to a server.
Yes. Drop a folder onto Convertessa or run convertessa ./outlines/ --to ipynb and every .opml file inside is converted in one pass, preserving the original filenames.
Yes. Convertessa strips OPML metadata during conversion, so the output .ipynb files contain only the outline content mapped to notebook cells.