Ink React TUI

Build interactive command-line interfaces using React components with Ink.

Quick Start

# Scaffold new project
npx create-ink-app my-cli
npx create-ink-app --typescript my-cli

# Or add to existing project
npm install ink react

Basic app:

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

const App = () => <Text color="green">Hello, CLI!</Text>;

render(<App />);

---

Core Components

Text

Display and style text. Only text nodes and nested <Text> allowed inside.

import {Text} from 'ink';

<Text color="green">Green text</Text>
<Text color="#005cc5">Hex color</Text>
<Text bold>Bold</Text>
<Text italic>Italic</Text>
<Text underline>Underlined</Text>
<Text strikethrough>Strikethrough</Text>
<Text inverse>Inverted colors</Text>
<Text dimColor>Dimmed</Text>
<Text backgroundColor="blue" color="white">With background</Text>

Text wrapping:

<Box width={10}>
  <Text wrap="truncate">Long text gets truncated…</Text>
  <Text wrap="truncate-middle">He…ld</Text>
  <Text wrap="truncate-start">…World</Text>
</Box>

Box

Flexbox container (like <div style="display: flex">).

import {Box, Text} from 'ink';

// Basic layout
<Box flexDirection="column" padding={1}>
  <Text>Row 1</Text>
  <Text>Row 2</Text>
</Box>

// With border
<Box borderStyle="round" borderColor="green" padding={1}>
  <Text>Bordered content</Text>
</Box>

// Flex alignment
<Box justifyContent="space-between" width={40}>
  <Text>Left</Text>
  <Text>Right</Text>
</Box>

Key properties:

• Dimensions: width, height, minWidth, minHeight
• Padding: padding, paddingX, paddingY, paddingTop, etc.
• Margin: margin, marginX, marginY, marginTop, etc.
• Flex: flexDirection, flexGrow, flexShrink, flexWrap, alignItems, justifyContent
• Borders: borderStyle (single, double, round, bold, classic), borderColor
• Background: backgroundColor
• Gap: gap, columnGap, rowGap

For full property reference, see references/components.md.

Newline & Spacer

import {Text, Newline, Spacer, Box} from 'ink';

// Newline inside Text
<Text>
  Line 1<Newline />Line 2<Newline count={2} />Line 4
</Text>

// Spacer fills available space
<Box width={40}>
  <Text>Left</Text>
  <Spacer />
  <Text>Right</Text>
</Box>

Static

Render permanent output above the dynamic UI (logs, completed tasks).

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

const App = ({completedTasks}) => (
  <>
    <Static items={completedTasks}>
      {task => (
        <Box key={task.id}>
          <Text color="green">✔ {task.title}</Text>
        </Box>
      )}
    </Static>
    <Box marginTop={1}>
      <Text dimColor>Processing...</Text>
    </Box>
  </>
);

Transform

Transform rendered text output.

import {Transform, Text} from 'ink';

<Transform transform={output => output.toUpperCase()}>
  <Text>hello world</Text>
</Transform>
// Output: HELLO WORLD

---

Essential Hooks

useInput

Handle keyboard input.

import {useInput, useApp} from 'ink';

const App = () => {
  const {exit} = useApp();

  useInput((input, key) => {
    if (input === 'q') exit();
    if (key.upArrow) { /* move up */ }
    if (key.downArrow) { /* move down */ }
    if (key.return) { /* select */ }
    if (key.escape) { /* cancel */ }
  });

  return <Text>Press q to quit, arrows to navigate</Text>;
};

Key properties: leftArrow, rightArrow, upArrow, downArrow, return, escape, ctrl, shift, tab, backspace, delete, pageUp, pageDown, meta.

Disable input capture: useInput(handler, {isActive: false}).

useApp

Control app lifecycle.

import {useApp} from 'ink';

const App = () => {
  const {exit} = useApp();
  
  // Exit after 5 seconds
  useEffect(() => {
    setTimeout(() => exit(), 5000);
  }, []);

  return <Text>Exiting soon...</Text>;
};

useFocus & useFocusManager

Manage focus between components.

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

const FocusableItem = ({label}) => {
  const {isFocused} = useFocus();
  
  return (
    <Box>
      <Text color={isFocused ? 'green' : undefined}>
        {isFocused ? '>' : ' '} {label}
      </Text>
    </Box>
  );
};

// Tab cycles focus, Shift+Tab goes backwards

Focus options: autoFocus, isActive, id.

For complete hooks reference, see references/hooks.md.

---

Common Patterns

Interactive List

import React, {useState} from 'react';
import {render, Box, Text, useInput, useApp} from 'ink';

const items = ['Option A', 'Option B', 'Option C'];

const SelectList = () => {
  const [selected, setSelected] = useState(0);
  const {exit} = useApp();

  useInput((input, key) => {
    if (key.upArrow) setSelected(s => Math.max(0, s - 1));
    if (key.downArrow) setSelected(s => Math.min(items.length - 1, s + 1));
    if (key.return) {
      console.log(`Selected: ${items[selected]}`);
      exit();
    }
    if (input === 'q') exit();
  });

  return (
    <Box flexDirection="column">
      {items.map((item, i) => (
        <Text key={item} color={i === selected ? 'green' : undefined}>
          {i === selected ? '>' : ' '} {item}
        </Text>
      ))}
    </Box>
  );
};

render(<SelectList />);

Progress Indicator

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

const ProgressBar = ({percent}) => {
  const width = 20;
  const filled = Math.round(width * percent / 100);
  
  return (
    <Box>
      <Text>[</Text>
      <Text color="green">{'█'.repeat(filled)}</Text>
      <Text>{'░'.repeat(width - filled)}</Text>
      <Text>] {percent}%</Text>
    </Box>
  );
};

const App = () => {
  const [progress, setProgress] = useState(0);

  useEffect(() => {
    const timer = setInterval(() => {
      setProgress(p => p >= 100 ? 100 : p + 10);
    }, 200);
    return () => clearInterval(timer);
  }, []);

  return <ProgressBar percent={progress} />;
};

render(<App />);

Task List with Static Output

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

const App = () => {
  const [completed, setCompleted] = useState([]);
  const [current, setCurrent] = useState('Task 1');

  useEffect(() => {
    const tasks = ['Task 1', 'Task 2', 'Task 3'];
    let i = 0;
    const timer = setInterval(() => {
      if (i < tasks.length) {
        setCompleted(prev => [...prev, {id: i, title: tasks[i]}]);
        i++;
        setCurrent(tasks[i] || 'Done!');
      }
    }, 1000);
    return () => clearInterval(timer);
  }, []);

  return (
    <>
      <Static items={completed}>
        {task => (
          <Text key={task.id} color="green">✔ {task.title}</Text>
        )}
      </Static>
      <Text color="yellow">⏳ {current}</Text>
    </>
  );
};

render(<App />);

---

Render API

import {render} from 'ink';

const {rerender, unmount, waitUntilExit, clear} = render(<App />);

// Update props
rerender(<App count={2} />);

// Programmatic exit
unmount();

// Wait for exit
await waitUntilExit();

// Clear output
clear();

Options:

render(<App />, {
  stdout: process.stdout,
  stdin: process.stdin,
  stderr: process.stderr,
  exitOnCtrlC: true,
  patchConsole: true,
  debug: false,
  maxFps: 30,
});

---

Testing

Use ink-testing-library:

import {render} from 'ink-testing-library';
import {Text} from 'ink';

const {lastFrame} = render(<Text>Hello</Text>);
expect(lastFrame()).toBe('Hello');

---

Useful Third-Party Components

Package	Purpose
ink-text-input	Text input field
ink-spinner	Loading spinners
ink-select-input	Select/dropdown
ink-progress-bar	Progress bars
ink-table	Data tables
ink-link	Terminal hyperlinks
ink-gradient	Gradient text
ink-big-text	Large ASCII text

For full list, see references/useful-components.md.