File Formats

On this page

Use an external folder
Format examples
Choose a format

Extension	Purpose
`.clro`	The application's standard note format; UTF-8 text.
`.md` / `.markdown`	Markdown-compatible notes; existing files are never renamed automatically.
`.tex`	Existing TeX source files.
`.txt` / `.csv`	Plain-text notes; `.csv` is not processed as a spreadsheet.
`.clrop`	Annotation data associated with a PDF, not a note.

Use an external folder

Register Temporary Paths to work with external files without copying them. Saving, renaming and moving affect the actual registered files. Removing a registration leaves originals intact. Ordinary use does not require startup JSON editing. Field names and manual editing are in the technical reference (Japanese).

Format examples

.clro is UTF-8 text that people write. For example, a file named research-notes.clro can contain the following Markdown text:

# Reading notes

- Check the figure on page 3.
- Review the annotations next time.

For .clrop, use the application's annotation tools rather than a text editor. Data structures (Japanese) contains JSON examples.

When annotating a PDF, the application creates a same-named .clrop file in the PDF's folder. Both the PDF and its .clrop file are required to view or edit annotations again. Move or share them together, and do not edit the .clrop manually or change its extension.

For the role and notation of .clro, see .clro Note Format. Choose what to share explains which files to send or export for editing in this application, reading in the companion viewer, or reading in another PDF application.

Choose a format

New structured notes: use .clro.
Notes exchanged with Markdown tools: use .md or .markdown; application-specific formatting may differ elsewhere.
Literal text: use .txt, or .csv to inspect/edit CSV as ordinary text without spreadsheet processing.
Existing TeX source: open .tex as source.
PDF annotations: let the app manage .clrop beside the PDF.

Existing files keep their extension unless you explicitly rename them. Renaming does not convert their contents. .clro and Markdown notes share supported formatting; plain text does not interpret Markdown, math or note links. Images imported as PNG/JPG/JPEG remain images until you request one-page PDF conversion.