Your files stay on your Mac.
Flat ODF Sheet is an XML-based spreadsheet format used by LibreOffice and other OpenDocument-compatible apps. Converting to CSV extracts the tabular cell data into plain comma-separated text that any spreadsheet app, database, or data pipeline can read directly. Convertessa runs entirely on your Mac — no file ever leaves your device.
Drag one or more .fods files into Convertessa, or point it at a folder to queue an entire batch at once.
Choose CSV from the output format list. Convertessa will extract the spreadsheet data into plain comma-separated text.
Click Convert. Your CSV files are saved alongside the originals — no upload, no account, no waiting on a server.
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.
Each sheet in the Flat ODF Sheet file is exported as a separate CSV file named after the original sheet. No data is silently dropped.
No. Convertessa runs fully offline on your Mac. Your files never leave your device — there is no server, no account, and no internet connection required.
No. Convertessa strips document metadata during conversion. The CSV output contains only cell values — no embedded author information or file properties.