Writing & notes

open-knowledge

Edit Markdown as comfortably as a Notion page, with files staying local

Visit official page 日本語で詳しく見る

Popularity

★ 3.5k

Last update

August 2026

License / pricing

GPL-3.0

What it does

A true WYSIWYG editor for Markdown files - you get the Notion or Google Docs writing experience without seeing the syntax, while the output remains ordinary Markdown on your own disk. It integrates with Claude, Codex and similar harnesses so an assistant can read and edit the same files. There is a macOS app plus a web UI; Windows users get the browser version. Integrations send note content to whichever provider you connect.

Summary based on the project's own description. The Japanese page has a fuller beginner guide: setup difficulty, what to prepare, and a step-by-step start.

Screenshots & visuals

Before you start

Setup difficultySome setup needed
Command lineNot required
API keyNot required
Sends data onlineYes

Judged automatically from the project's own metadata. Always confirm on the official page.

open-knowledge FAQ

Is open-knowledge free?: Yes. It runs on your own machine, so there is no usage-based cost either.
Do I need to install anything or write code to use open-knowledge?: You install it like a normal desktop app. No command line involved.
Does open-knowledge work on a phone?: No. It needs a computer.
Can I use open-knowledge commercially?: The licence is GPL-3.0. Using it commercially is fine, but if you distribute something built on it you may be required to release that under the same licence. Keep it internal, or check before distributing.

How it compares

The conditions that decide whether you can actually use it, side by side.

Tool	Command line	API key	Sends data out	Phone	Commercial use
open-knowledge (this page)	Not needed	Not needed	Yes	No	Yes
joplin	Not needed	Not needed	Yes	No	Not verified
markmap	Not needed	Not needed	No	No	Yes
reflect-open	Not needed	Required	Yes	Yes	Yes

"Sends data out" means your input is uploaded to someone's server. Pick "No" when the material cannot leave your organisation.

Other writing & notes tools

joplin

A free, open-source Markdown notebook with to-dos

markmap

Turns Markdown outlines into mindmaps

reflect-open

Notes that stay as plain Markdown files, for Mac and iPhone

Lumina-Note

A Markdown workspace where an agent can work across the whole vault

Browse all tools Home

What it does

Summary based on the project's own description. The Japanese page has a fuller beginner guide: setup difficulty, what to prepare, and a step-by-step start.

open-knowledge FAQ

Is open-knowledge free?

Yes. It runs on your own machine, so there is no usage-based cost either.

Do I need to install anything or write code to use open-knowledge?

You install it like a normal desktop app. No command line involved.

Does open-knowledge work on a phone?

No. It needs a computer.

Can I use open-knowledge commercially?

The licence is GPL-3.0. Using it commercially is fine, but if you distribute something built on it you may be required to release that under the same licence. Keep it internal, or check before distributing.

How it compares

The conditions that decide whether you can actually use it, side by side.

Tool	Command line	API key	Sends data out	Phone	Commercial use
open-knowledge (this page)	Not needed	Not needed	Yes	No	Yes
joplin	Not needed	Not needed	Yes	No	Not verified
markmap	Not needed	Not needed	No	No	Yes
reflect-open	Not needed	Required	Yes	Yes	Yes

"Sends data out" means your input is uploaded to someone's server. Pick "No" when the material cannot leave your organisation.