Your files stay on your Mac.
Convertessa reads each .ipynb file and maps its Markdown cell headings — H1 through H6 — into a nested OPML outline. The resulting .opml file opens in any outline editor, RSS reader, or tool that ingests OPML. Every step runs on your Mac; files are never uploaded.
Drag one .ipynb file or an entire folder of notebooks onto Convertessa. Use File > Open to browse if you prefer.
Choose OPML from the output format list. Convertessa targets the standard OPML 2.0 specification.
Click Convert. Convertessa writes one .opml file per notebook, preserving the heading hierarchy found in each source file.
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.
Convertessa maps Markdown headings (#, ##, ###, and so on) to nested <outline> elements. Code cells and cell outputs are not included — only the structural headings from Markdown cells.
Yes. Kernel metadata, execution counts, and cell outputs are not carried into the OPML file. The output contains only the outline structure derived from your Markdown headings.
Yes. Drag a folder onto Convertessa or run convertessa ./notebooks/ --to opml in the terminal. Convertessa processes every .ipynb file in the folder and writes a matching .opml file for each one.