Your files stay on your Mac.
Convertessa parses your Markdown files and re-emits them as Djot, a formally specified lightweight markup format with unambiguous parsing rules. Structure — headings, lists, fenced code blocks, links, and emphasis — is mapped directly across. Your files stay on your Mac; nothing is uploaded.
Drag one .md file or an entire folder onto Convertessa. Batch mode processes every Markdown file in the folder in a single pass.
Choose Djot from the output format list. Convertessa maps standard Markdown syntax — headings, lists, code blocks, links, emphasis — to their Djot equivalents.
Click Convert. Djot files are written next to the originals. Conversion runs entirely on your Mac — no cloud round-trip, no upload.
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.
Djot is a lightweight markup language with a single, unambiguous specification, created as a formally defined alternative to Markdown. The syntax is similar — headings, lists, links, code blocks — but parsing edge cases that produce inconsistent output across Markdown implementations are resolved deterministically in Djot.
Standard constructs convert cleanly: ATX headings, fenced and indented code blocks, bullet and ordered lists, emphasis, strong, inline code, and links. Non-standard Markdown extensions without a direct Djot equivalent are passed through unchanged.
Yes. Drop a folder onto Convertessa or run convertessa ./folder/ --to djot to batch-convert every .md file in one pass. Output Djot files are written alongside the originals.