Ketcher

An Obsidian desktop plugin for viewing and drawing chemical structures and reactions with Ketcher, a web-based molecule sketcher.

Installation

One-click installation: Add Ketcher to Obsidian

or install from Obsidian under Settings → Community plugins.

Get started

Select the Ketcher ribbon icon to create a new .ket file. New files are saved to the folder configured under Settings → Ketcher → Ketcher folder.

Link to a structure with [[example.ket]]; hovering the link displays a read-only structure preview. Embed a structure directly in a note with ![[example.ket]]; click the preview to open it in Ketcher. Both forms work in Live Preview and Reading view.

For editor features and shortcuts, see the Ketcher user guide.

Development

Development requires Node.js 24.14.1 or newer and npm.

npm ci
npm run dev

Run the production checks before committing:

npm run build
npm run lint

The production build creates the three release assets at the repository root: main.js, manifest.json, and styles.css.

Releasing

The release workflow follows the Obsidian GitHub Actions release guide.

Before the first release, open GitHub → Settings → Actions → General → Workflow permissions, select Read and write permissions, and save.

Bump the version

Use npm version. The repository's version lifecycle script also synchronizes manifest.json and versions.json.

npm version patch # 0.2.0 -> 0.2.1
npm version minor # 0.2.0 -> 0.3.0
npm version major # 0.2.0 -> 1.0.0

then

git push origin 0.2.0
git push