Proofreader

AI-based proofreading and stylistic improvements for your writing. Changes are inserted as suggestions directly in the editor, similar to the suggested changes feature in word processing apps.

Table of contents

• Features
• Installation & setup
  • Plugin installation
  • Get an OpenAI API key
• Usage
• Visual appearance of the changes
• Plugin development
• About the developer

Features

• Suggested changes are inserted directly into the text: Additions as ==highlights== and removals as ~~strikethroughs~~.
• Accept or reject changes with just one hotkey.
• Easy to use: No complicated plugin settings and AI parameters to configure.

	Professional proofreading service	Proofreader plugin
Cost for English text of 10,000 words	~ $400, depending on the service	~ $0.01 – $0.061
Completion duration	up to 3 work days	about 5 minutes
Input format	usually Microsoft Word (.docx)	Markdown file in Obsidian
Method of incorporating changes	mostly mouse clicks	keyboard shortcuts
Additional benefits	Editor makes general comments on writing style.	Plugin can also be used to quickly proofread single sentences or paragraphs.

Note

This plugin requires an OpenAI API key and incurs costs at OpenAI based on usage. Network requests are made when running the proofreading command.

Installation & setup

Plugin installation

Install in Obsidian

Get an OpenAI API key

1. Create an OpenAI account.
2. Go to this site, and click Create new secret key.
3. Copy the API key.
4. In Obsidian, go to Settings → Proofreader and paste your API key there.

Usage

1. Use the command Proofread selection/paragraph to check the selected text. If there is no selection, the command will check the current paragraph (line). Alternatively, you can also check the whole document with Proofread full document.
2. The changes are automatically inserted.
3. Accept/reject changes with the Accept suggestions in selection/paragraph. Same as the proofreading command, the accept and reject commands affect the current paragraph if there is no selection. Alternatively, you can also only accept/reject the next suggestion after your cursor via Accept next suggestion.

Tip

The usage costs should not be very high, nonetheless you can track them on this page.

Visual appearance of the changes

You can add the following CSS snippet to make highlights and strikethroughs appear like suggested changes, similar to the screenshot further above. (How to add CSS snippets.)

.cm-strikethrough {
	text-decoration-color: var(--color-red);
}

.cm-s-obsidian span.cm-highlight {
	background-color: rgba(var(--color-green-rgb), 35%);
}

Testimonials

I was paying $29 a month for type.ai until today, your plugin made me cancel the subscription, because the only feature I wanted from there was this inline granular diffing which no other app offered, until Proofreader. @samwega

Plugin development

just init   # run once after cloning

just format # run all formatters
just build  # builds the plugin
just check  # runs the pre-commit hook (without committing)

Note

This repo uses a pre-commit hook, which prevents commits that do not build or do not pass the checks.

About the developer

In my day job, I am a sociologist studying the social mechanisms underlying the digital economy. For my PhD project, I investigate the governance of the app economy and how software ecosystems manage the tension between innovation and compatibility. If you are interested in this subject, feel free to get in touch.

• Academic website
• ResearchGate
• Mastodon
• LinkedIn

Footnotes

1. Estimated pricing for the GPT 4.1 mini and nano models in April 2025. The plugin developer is not responsible if the actual costs differ. You can track your usage costs on this page. ↩