Your files stay on your Mac.
Convertessa rewrites Markdown markup into Emacs Muse syntax — translating headings, inline emphasis, links, and lists into the format Emacs Muse mode expects. The result is a .muse file you can open and publish directly inside Emacs. All processing runs locally on your Mac; no file is ever uploaded anywhere.
Drag one .md file or an entire folder into Convertessa. The app lists every Markdown document queued for conversion.
Choose Emacs Muse from the output format list. Convertessa maps it to .muse and schedules every file in the queue.
Click Convert. Convertessa writes a .muse file for each source document, stripping embedded metadata in the process.
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.
Headings (# through ######), bold, italic, inline code, hyperlinks, and unordered and ordered lists are all mapped to their Emacs Muse equivalents. Elements with no direct Muse counterpart are preserved as plain text.
Yes. Drag a folder onto Convertessa or run convertessa ./folder/ --to muse to batch-convert every Markdown file inside. Convertessa writes one .muse file per source document.
No. Convertessa runs entirely on your Mac. Your Markdown files are never transmitted to any server or third-party service.