ink

React for CLIs. Build and test your CLI output using components.

Ink provides the same component-based UI building experience that React offers in the browser, but for command-line apps. It uses Yoga to build Flexbox layouts in the terminal, so most CSS-like properties are available in Ink as well. If you are already familiar with React, you already know Ink.

Since Ink is a React renderer, all features of React are supported. Head over to the React website for documentation on how to use it. Only Ink's methods are documented in this readme.

Fully AI-generated pull requests are not accepted. You can use AI, but should be verified and cleaned up by a human. Only Opus 4.6+ (high-effort) and Codex 5.4+ (extra high) are accepted models. Preferably created with Opus and verified by Codex.

^{My open source work is supported by the community ❤️}

Install

npm install ink react

Note

This readme documents the upcoming version of Ink. For the latest stable release, see Ink on npm.

Usage

import React, {useState, useEffect} from 'react';
import {render, Text} from 'ink';

const Counter = () => {
	const [counter, setCounter] = useState(0);

	useEffect(() => {
		const timer = setInterval(() => {
			setCounter(previousCounter => previousCounter + 1);
		}, 100);

		return () => {
			clearInterval(timer);
		};
	}, []);

	return <Text color="green">{counter} tests passed</Text>;
};

render(<Counter />);

Who's Using Ink?

• Claude Code - An agentic coding tool made by Anthropic.
• Gemini CLI - An agentic coding tool made by Google.
• GitHub Copilot CLI - Just say what you want the shell to do.
• Canva CLI - CLI for creating and managing Canva Apps.
• Cloudflare's Wrangler - The CLI for Cloudflare Workers.
• Linear - Linear built an internal CLI for managing deployments, configs, and other housekeeping tasks.
• Gatsby - Gatsby is a modern web framework for blazing-fast websites.
• tap - A Test-Anything-Protocol library for JavaScript.
• Terraform CDK - Cloud Development Kit (CDK) for HashiCorp Terraform.
• Specify CLI - Automate the distribution of your design tokens.
• Twilio's SIGNAL - CLI for Twilio's SIGNAL conference. Blog post.
• Typewriter - Generates strongly-typed Segment analytics clients from arbitrary JSON Schema.
• Prisma - The unified data layer for modern applications.
• Blitz - The Fullstack React Framework.
• New York Times - NYT uses Ink's kyt - a toolkit that encapsulates and manages the configuration for web apps.
• tink - A next-generation runtime and package manager.
• Inkle - A Wordle game.
• loki - Visual regression testing tool for Storybook.
• Bit - Build, distribute, and collaborate on components.
• Remirror - Your friendly, world-class editor toolkit.
• Prime - Open-source GraphQL CMS.
• emoj - Find relevant emojis.
• emma - Find and install npm packages easily.
• npm-check-extras - Check for outdated and unused dependencies, and run update/delete actions on selected ones.
• swiff - Multi-environment command-line tools for time-saving web developers.
• share - Share files quickly.
• Kubelive - A CLI for Kubernetes that provides live data about the cluster and its resources.
• changelog-view - View changelogs.
• cfpush - Interactive Cloud Foundry tutorial.
• startd - Turn your React component into a web app.
• wiki-cli - Search Wikipedia and read article summaries.
• garson - Build interactive, config-based command-line interfaces.
• git-contrib-calendar - Display a contributions calendar for any Git repository.
• gitgud - Interactive command-line GUI for Git.
• Autarky - Find and delete old node_modules directories to free up disk space.
• fast-cli - Test your download and upload speeds.
• tasuku - Minimal task runner.
• mnswpr - A Minesweeper game.
• lrn - Learning by repetition.
• turdle - A Wordle game.
• Shopify CLI - Build apps, themes, and storefronts for the Shopify platform.
• ToDesktop CLI - All-in-one platform for building Electron apps.
• Walle - A full-featured crypto wallet for EVM networks.
• Sudoku - A Sudoku game.
• Sea Trader - A Taipan!-inspired trading simulator game.
• srtd - Live-reloading SQL templates for Supabase projects.
• tweakcc - Customize your Claude Code styling.
• argonaut - Manage Argo CD resources.
• Qodo Command - Build, run, and manage AI agents.
• Nanocoder - A community-built, local-first AI coding agent with multi-provider support.
• dev3000 - An AI agent MCP orchestrator and developer browser.
• Neovate Code - An agentic coding tool made by AntGroup.
• instagram-cli - Instagram client.
• ElevenLabs CLI - ElevenLabs agents client.
• SSH AI Chat - Chat with AI over SSH.
• Deep Code CLI - AI coding assistant optimized for the DeepSeek model.

(PRs welcome. Append new entries at the end. Repos must have 100+ stars and showcase Ink beyond a basic list picker.)

Contents

• Getting Started
• App Lifecycle
• Components
  • <Text>
  • <Box>
  • <Newline>
  • <Spacer>
  • <Static>
  • <Transform>
• Hooks
  • useInput
  • usePaste
  • useApp
  • useStdin
  • useStdout
  • useBoxMetrics
  • useStderr
  • useWindowSize
  • useFocus
  • useFocusManager
  • useCursor
  • useAnimation
• API
• Testing
• Using React Devtools
• Screen Reader Support
• Useful Components
• Useful Hooks
• Recipes
• Examples
• Continuous Integration

Getting Started

Use create-ink-app to quickly scaffold a new Ink-based CLI.

npx create-ink-app my-ink-cli

Alternatively, create a TypeScript project:

npx create-ink-app --typescript my-ink-cli

npm install --save-dev @babel/preset-react

{
	"presets": ["@babel/preset-react"]
}

import React from 'react';
import {render, Text} from 'ink';

const Demo = () => <Text>Hello World</Text>;

render(<Demo />);

npx babel source.js -o cli.js

node cli

Ink uses Yoga, a Flexbox layout engine, to build great user interfaces for your CLIs using familiar CSS-like properties you've used when building apps for the browser. It's important to remember that each element is a Flexbox container. Think of it as if every <div> in the browser had display: flex. See <Box> built-in component below for documentation on how to use Flexbox layouts in Ink. Note that all text must be wrapped in a <Text> component.

App Lifecycle

An Ink app is a Node.js process, so it stays alive only while there is active work in the event loop (timers, pending promises, useInput listening on stdin, etc.). If your component tree has no async work, the app will render once and exit immediately.

To exit the app, press Ctrl+C (enabled by default via exitOnCtrlC), call exit() from useApp inside a component, or call unmount() on the object returned by render().

Use waitUntilExit() to run code after the app is unmounted:

const {waitUntilExit} = render(<MyApp />);

await waitUntilExit();

console.log('App exited');

Components

<Text>

This component can display text and change its style to make it bold, underlined, italic, or strikethrough.

import {render, Text} from 'ink';

const Example = () => (
	<>
		<Text color="green">I am green</Text>
		<Text color="black" backgroundColor="white">
			I am black on white
		</Text>
		<Text color="#ffffff">I am white</Text>
		<Text bold>I am bold</Text>
		<Text italic>I am italic</Text>
		<Text underline>I am underline</Text>
		<Text strikethrough>I am strikethrough</Text>
		<Text inverse>I am inversed</Text>
	</>
);

render(<Example />);

Note

<Text> allows only text nodes and nested <Text> components inside of it. For example, <Box> component can't be used inside <Text>.

color

Type: string

Change text color. Ink uses chalk under the hood, so all its functionality is supported.

<Text color="green">Green</Text>
<Text color="#005cc5">Blue</Text>
<Text color="rgb(232, 131, 136)">Red</Text>

backgroundColor

Type: string

Same as color above, but for background.

<Text backgroundColor="green" color="white">Green</Text>
<Text backgroundColor="#005cc5" color="white">Blue</Text>
<Text backgroundColor="rgb(232, 131, 136)" color="white">Red</Text>

dimColor

Type: boolean
Default: false

Dim the color (make it less bright).

<Text color="red" dimColor>
	Dimmed Red
</Text>

bold

Type: boolean
Default: false

Make the text bold.

italic

Type: boolean
Default: false

Make the text italic.

underline

Type: boolean
Default: false

Make the text underlined.

strikethrough

Type: boolean
Default: false

Make the text crossed with a line.

inverse

Type: boolean
Default: false

Invert background and foreground colors.

<Text inverse color="yellow">
	Inversed Yellow
</Text>

wrap

Type: string
Allowed values: wrap hard truncate truncate-start truncate-middle truncate-end
Default: wrap

This property tells Ink to wrap or truncate text if its width is larger than the container. If wrap is passed (the default), Ink will wrap text and split it into multiple lines. If hard is passed, Ink will fill each line to the full column width, breaking words as necessary. If truncate-* is passed, Ink will truncate text instead, resulting in one line of text with the rest cut off.

<Box width={7}>
	<Text>Hello World</Text>
</Box>
//=> 'Hello\nWorld'

<Box width={7}>
	<Text wrap="hard">Hello World</Text>
</Box>
//=> 'Hello W\norld'

// `truncate` is an alias to `truncate-end`
<Box width={7}>
	<Text wrap="truncate">Hello World</Text>
</Box>
//=> 'Hello…'

<Box width={7}>
	<Text wrap="truncate-middle">Hello World</Text>
</Box>
//=> 'He…ld'

<Box width={7}>
	<Text wrap="truncate-start">Hello World</Text>
</Box>
//=> '…World'

<Box>

<Box> is an essential Ink component to build your layout. It's like <div style="display: flex"> in the browser.

import {render, Box, Text} from 'ink';

const Example = () => (
	<Box margin={2}>
		<Text>This is a box with margin</Text>
	</Box>
);

render(<Example />);

Dimensions

width

Type: number string

Width of the element in spaces. You can also set it as a percentage, which will calculate the width based on the width of the parent element.

<Box width={4}>
	<Text>X</Text>
</Box>
//=> 'X   '

<Box width={10}>
	<Box width="50%">
		<Text>X</Text>
	</Box>
	<Text>Y</Text>
</Box>
//=> 'X    Y'

height

Type: number string

Height of the element in lines (rows). You can also set it as a percentage, which will calculate the height based on the height of the parent element.

<Box height={4}>
	<Text>X</Text>
</Box>
//=> 'X\n\n\n'

<Box height={6} flexDirection="column">
	<Box height="50%">
		<Text>X</Text>
	</Box>
	<Text>Y</Text>
</Box>
//=> 'X\n\n\nY\n\n'

minWidth

Type: number

Sets a minimum width of the element. Percentages aren't supported yet; see react/yoga#872.

minHeight

Type: number string

Sets a minimum height of the element in lines (rows). You can also set it as a percentage, which will calculate the minimum height based on the height of the parent element.

maxWidth

Type: number

Sets a maximum width of the element. Percentages aren't supported yet; see react/yoga#872.

maxHeight

Type: number string

Sets a maximum height of the element in lines (rows). You can also set it as a percentage, which will calculate the maximum height based on the height of the parent element.

aspectRatio

Type: number

Defines the aspect ratio (width/height) for the element.

Use it with at least one size constraint (width, height, minHeight, or maxHeight) so Ink can derive the missing dimension.

Padding

paddingTop

Type: number
Default: 0

Top padding.

paddingBottom

Type: number
Default: 0

Bottom padding.

paddingLeft

Type: number
Default: 0

Left padding.

paddingRight

Type: number
Default: 0

Right padding.

paddingX

Type: number
Default: 0

Horizontal padding. Equivalent to setting paddingLeft and paddingRight.

paddingY

Type: number
Default: 0

Vertical padding. Equivalent to setting paddingTop and paddingBottom.

padding

Type: number
Default: 0

Padding on all sides. Equivalent to setting paddingTop, paddingBottom, paddingLeft and paddingRight.

<Box paddingTop={2}><Text>Top</Text></Box>
<Box paddingBottom={2}><Text>Bottom</Text></Box>
<Box paddingLeft={2}><Text>Left</Text></Box>
<Box paddingRight={2}><Text>Right</Text></Box>
<Box paddingX={2}><Text>Left and right</Text></Box>
<Box paddingY={2}><Text>Top and bottom</Text></Box>
<Box padding={2}><Text>Top, bottom, left and right</Text></Box>

Margin

marginTop

Type: number
Default: 0

Top margin.

marginBottom

Type: number
Default: 0

Bottom margin.

marginLeft

Type: number
Default: 0

Left margin.

marginRight

Type: number
Default: 0

Right margin.

marginX

Type: number
Default: 0

Horizontal margin. Equivalent to setting marginLeft and marginRight.

marginY

Type: number
Default: 0

Vertical margin. Equivalent to setting marginTop and marginBottom.

margin

Type: number
Default: 0

Margin on all sides. Equivalent to setting marginTop, marginBottom, marginLeft and marginRight.

<Box marginTop={2}><Text>Top</Text></Box>
<Box marginBottom={2}><Text>Bottom</Text></Box>
<Box marginLeft={2}><Text>Left</Text></Box>
<Box marginRight={2}><Text>Right</Text></Box>
<Box marginX={2}><Text>Left and right</Text></Box>
<Box marginY={2}><Text>Top and bottom</Text></Box>
<Box margin={2}><Text>Top, bottom, left and right</Text></Box>

Gap

gap

Type: number
Default: 0

Size of the gap between an element's columns and rows. A shorthand for columnGap and rowGap.

<Box gap={1} width={3} flexWrap="wrap">
	<Text>A</Text>
	<Text>B</Text>
	<Text>C</Text>
</Box>
// A B
//
// C

columnGap

Type: number
Default: 0

Size of the gap between an element's columns.

<Box columnGap={1}>
	<Text>A</Text>
	<Text>B</Text>
</Box>
// A B

rowGap

Type: number
Default: 0

Size of the gap between an element's rows.

<Box flexDirection="column" rowGap={1}>
	<Text>A</Text>
	<Text>B</Text>
</Box>
// A
//
// B

Flex

flexGrow

Type: number
Default: 0

See flex-grow.

<Box>
	<Text>Label:</Text>
	<Box flexGrow={1}>
		<Text>Fills all remaining space</Text>
	</Box>
</Box>

flexShrink

Type: number
Default: 1

See flex-shrink.

<Box width={20}>
	<Box flexShrink={2} width={10}>
		<Text>Will be 1/4</Text>
	</Box>
	<Box width={10}>
		<Text>Will be 3/4</Text>
	</Box>
</Box>

flexBasis

Type: number string

See flex-basis.

<Box width={6}>
	<Box flexBasis={3}>
		<Text>X</Text>
	</Box>
	<Text>Y</Text>
</Box>
//=> 'X  Y'

<Box width={6}>
	<Box flexBasis="50%">
		<Text>X</Text>
	</Box>
	<Text>Y</Text>
</Box>
//=> 'X  Y'

flexDirection

Type: string
Allowed values: row row-reverse column column-reverse

See flex-direction.

<Box>
	<Box marginRight={1}>
		<Text>X</Text>
	</Box>
	<Text>Y</Text>
</Box>
// X Y

<Box flexDirection="row-reverse">
	<Text>X</Text>
	<Box marginRight={1}>
		<Text>Y</Text>
	</Box>
</Box>
// Y X

<Box flexDirection="column">
	<Text>X</Text>
	<Text>Y</Text>
</Box>
// X
// Y

<Box flexDirection="column-reverse">
	<Text>X</Text>
	<Text>Y</Text>
</Box>
// Y
// X

flexWrap

Type: string
Allowed values: nowrap wrap wrap-reverse

See flex-wrap.

<Box width={2} flexWrap="wrap">
	<Text>A</Text>
	<Text>BC</Text>
</Box>
// A
// B C

<Box flexDirection="column" height={2} flexWrap="wrap">
	<Text>A</Text>
	<Text>B</Text>
	<Text>C</Text>
</Box>
// A C
// B

alignItems

Type: string
Allowed values: flex-start center flex-end stretch baseline

See align-items.

<Box alignItems="flex-start">
	<Box marginRight={1}>
		<Text>X</Text>
	</Box>
	<Text>
		A
		<Newline/>
		B
		<Newline/>
		C
	</Text>
</Box>
// X A
//   B
//   C

<Box alignItems="center">
	<Box marginRight={1}>
		<Text>X</Text>
	</Box>
	<Text>
		A
		<Newline/>
		B
		<Newline/>
		C
	</Text>
</Box>
//   A
// X B
//   C

<Box alignItems="flex-end">
	<Box marginRight={1}>
		<Text>X</Text>
	</Box>
	<Text>
		A
		<Newline/>
		B
		<Newline/>
		C
	</Text>
</Box>
//   A
//   B
// X C

alignSelf

Type: string
Default: auto
Allowed values: auto flex-start center flex-end stretch baseline

See align-self.

<Box height={3}>
	<Box alignSelf="flex-start">
		<Text>X</Text>
	</Box>
</Box>
// X
//
//

<Box height={3}>
	<Box alignSelf="center">
		<Text>X</Text>
	</Box>
</Box>
//
// X
//

<Box height={3}>
	<Box alignSelf="flex-end">
		<Text>X</Text>
	</Box>
</Box>
//
//
// X

alignContent

Type: string
Default: flex-start
Allowed values: flex-start flex-end center stretch space-between space-around space-evenly

Defines alignment between flex lines on the cross axis when flexWrap creates multiple lines. See align-content. Unlike CSS (stretch), Ink defaults to flex-start so wrapped lines stay compact and fixed-height boxes don't gain unexpected empty rows unless you opt in to stretching.

justifyContent

Type: string
Allowed values: flex-start center flex-end space-between space-around space-evenly

See justify-content.

<Box justifyContent="flex-start">
	<Text>X</Text>
</Box>
// [X      ]

<Box justifyContent="center">
	<Text>X</Text>
</Box>
// [   X   ]

<Box justifyContent="flex-end">
	<Text>X</Text>
</Box>
// [      X]

<Box justifyContent="space-between">
	<Text>X</Text>
	<Text>Y</Text>
</Box>
// [X      Y]

<Box justifyContent="space-around">
	<Text>X</Text>
	<Text>Y</Text>
</Box>
// [  X   Y  ]

<Box justifyContent="space-evenly">
	<Text>X</Text>
	<Text>Y</Text>
</Box>
// [   X   Y   ]

Position

position

Type: string
Allowed values: relative absolute static
Default: relative

Controls how the element is positioned.

When position is static, top, right, bottom, and left are ignored.

top

Type: number string

Top offset for positioned elements. You can also set it as a percentage of the parent size.

right

Type: number string

Right offset for positioned elements. You can also set it as a percentage of the parent size.

bottom

Type: number string

Bottom offset for positioned elements. You can also set it as a percentage of the parent size.

left

Type: number string

Left offset for positioned elements. You can also set it as a percentage of the parent size.

Visibility

display

Type: string
Allowed values: flex none
Default: flex

Set this property to none to hide the element.

overflowX

Type: string
Allowed values: visible hidden
Default: visible

Behavior for an element's overflow in the horizontal direction.

overflowY

Type: string
Allowed values: visible hidden
Default: visible

Behavior for an element's overflow in the vertical direction.

overflow

Type: string
Allowed values: visible hidden
Default: visible

A shortcut for setting overflowX and overflowY at the same time.

Borders

borderStyle

Type: string
Allowed values: single double round bold singleDouble doubleSingle classic | BoxStyle

Add a border with a specified style. If borderStyle is undefined (the default), no border will be added. Ink uses border styles from the cli-boxes module.

<Box flexDirection="column">
	<Box>
		<Box borderStyle="single" marginRight={2}>
			<Text>single</Text>
		</Box>

		<Box borderStyle="double" marginRight={2}>
			<Text>double</Text>
		</Box>

		<Box borderStyle="round" marginRight={2}>
			<Text>round</Text>
		</Box>

		<Box borderStyle="bold">
			<Text>bold</Text>
		</Box>
	</Box>

	<Box marginTop={1}>
		<Box borderStyle="singleDouble" marginRight={2}>
			<Text>singleDouble</Text>
		</Box>

		<Box borderStyle="doubleSingle" marginRight={2}>
			<Text>doubleSingle</Text>
		</Box>

		<Box borderStyle="classic">
			<Text>classic</Text>
		</Box>
	</Box>
</Box>

Alternatively, pass a custom border style like so:

<Box
	borderStyle={{
		topLeft: '↘',
		top: '↓',
		topRight: '↙',
		left: '→',
		bottomLeft: '↗',
		bottom: '↑',
		bottomRight: '↖',
		right: '←',
	}}
>
	<Text>Custom</Text>
</Box>

See example in examples/borders.

borderColor

Type: string

Change border color. A shorthand for setting borderTopColor, borderRightColor, borderBottomColor, and borderLeftColor.

<Box borderStyle="round" borderColor="green">
	<Text>Green Rounded Box</Text>
</Box>

borderTopColor

Type: string

Change top border color. Accepts the same values as color in <Text> component.

<Box borderStyle="round" borderTopColor="green">
	<Text>Hello world</Text>
</Box>

borderRightColor

Type: string

Change the right border color. Accepts the same values as color in <Text> component.

<Box borderStyle="round" borderRightColor="green">
	<Text>Hello world</Text>
</Box>

borderBottomColor

Type: string

Change the bottom border color. Accepts the same values as color in <Text> component.

<Box borderStyle="round" borderBottomColor="green">
	<Text>Hello world</Text>
</Box>

borderLeftColor

Type: string

Change the left border color. Accepts the same values as color in <Text> component.

<Box borderStyle="round" borderLeftColor="green">
	<Text>Hello world</Text>
</Box>

borderDimColor

Type: boolean
Default: false

Dim the border color. A shorthand for setting borderTopDimColor, borderBottomDimColor, borderLeftDimColor, and borderRightDimColor.

<Box borderStyle="round" borderDimColor>
	<Text>Hello world</Text>
</Box>

borderTopDimColor

Type: boolean
Default: false

Dim the top border color.

<Box borderStyle="round" borderTopDimColor>
	<Text>Hello world</Text>
</Box>

borderBottomDimColor

Type: boolean
Default: false

Dim the bottom border color.

<Box borderStyle="round" borderBottomDimColor>
	<Text>Hello world</Text>
</Box>

borderLeftDimColor

Type: boolean
Default: false

Dim the left border color.

<Box borderStyle="round" borderLeftDimColor>
	<Text>Hello world</Text>
</Box>

borderRightDimColor

Type: boolean
Default: false

Dim the right border color.

<Box borderStyle="round" borderRightDimColor>
	<Text>Hello world</Text>
</Box>

borderBackgroundColor

Type: string

Change border background color. Accepts the same values as backgroundColor in <Text> component. A shorthand for setting borderTopBackgroundColor, borderRightBackgroundColor, borderBottomBackgroundColor, and borderLeftBackgroundColor.

<Box borderStyle="round" borderColor="white" borderBackgroundColor="green">
	<Text>Hello world</Text>
</Box>

borderTopBackgroundColor

Type: string

Change top border background color. Accepts the same values as backgroundColor in <Text> component. Falls back to borderBackgroundColor if not specified.

<Box borderStyle="round" borderColor="white" borderTopBackgroundColor="green">
	<Text>Hello world</Text>
</Box>

borderBottomBackgroundColor

Type: string

Change bottom border background color. Accepts the same values as backgroundColor in <Text> component. Falls back to borderBackgroundColor if not specified.

<Box
	borderStyle="round"
	borderColor="white"
	borderBottomBackgroundColor="green"
>
	<Text>Hello world</Text>
</Box>

borderRightBackgroundColor

Type: string

Change right border background color. Accepts the same values as backgroundColor in <Text> component. Falls back to borderBackgroundColor if not specified.

<Box borderStyle="round" borderColor="white" borderRightBackgroundColor="green">
	<Text>Hello world</Text>
</Box>

borderLeftBackgroundColor

Type: string

Change left border background color. Accepts the same values as backgroundColor in <Text> component. Falls back to borderBackgroundColor if not specified.

<Box borderStyle="round" borderColor="white" borderLeftBackgroundColor="green">
	<Text>Hello world</Text>
</Box>

borderTop

Type: boolean
Default: true

Determines whether the top border is visible.

borderRight

Type: boolean
Default: true

Determines whether the right border is visible.

borderBottom

Type: boolean
Default: true

Determines whether the bottom border is visible.

borderLeft

Type: boolean
Default: true

Determines whether the left border is visible.

Background

backgroundColor

Type: string

Background color for the element.

Accepts the same values as color in the <Text> component.