vt100.js

Pure TypeScript VT100 terminal emulator. Zero dependencies, headless, fast.

Part of the vterm monorepo.

Features

• Full VT100/ANSI escape sequence parsing
• SGR attributes (bold, italic, underline styles, colors, strikethrough, etc.)
• 16-color, 256-color, and 24-bit truecolor support
• Cursor movement, save/restore (DECSC/DECRC)
• Screen modes (alternate screen, auto-wrap, origin mode, etc.)
• Scroll regions (DECSTBM) with content preservation
• Scrollback buffer with configurable limit
• Insert/delete characters and lines
• Wide character support (CJK, emoji)
• Zero dependencies — works in Bun, Node.js, and browsers

Install

npm install vt100.js

Usage

import { createVt100Screen } from "vt100.js"

const screen = createVt100Screen({ cols: 80, rows: 24 })
screen.process(new TextEncoder().encode("Hello, \x1b[1mBold\x1b[0m World!"))

console.log(screen.getText()) // "Hello, Bold World!"
console.log(screen.getCell(0, 7).bold) // true
console.log(screen.getCursorPosition()) // { x: 18, y: 0 }

API

createVt100Screen(options)

| Option | Type | Default | Description | | ----------------- | -------- | -------- | -------------------- | | cols | number | required | Terminal width | | rows | number | required | Terminal height | | scrollbackLimit | number | 1000 | Max scrollback lines |

Screen methods

| Method | Description | | ------------------------------ | ---------------------------------- | | process(data: Uint8Array) | Feed raw terminal data | | getText() | Get all text (scrollback + screen) | | getTextRange(sr, sc, er, ec) | Get text in a range | | getLine(row) | Get cells for a row | | getCell(row, col) | Get a single cell | | getCursorPosition() | Get cursor { x, y } | | getCursorVisible() | Check cursor visibility | | getMode(mode) | Check terminal mode | | getTitle() | Get window title | | getScrollbackLength() | Number of scrollback lines | | getViewportOffset() | Current viewport scroll offset | | scrollViewport(delta) | Scroll viewport | | resize(cols, rows) | Resize terminal | | reset() | Reset to initial state |

Cell properties

interface ScreenCell {
  char: string
  fg: CellColor | null // { r, g, b }
  bg: CellColor | null
  bold: boolean
  faint: boolean
  italic: boolean
  underline: "none" | "single" | "double" | "curly" | "dotted" | "dashed"
  strikethrough: boolean
  inverse: boolean
  hidden: boolean
  wide: boolean
}

See also

• vterm.js — full-featured modern emulator (100% terminfo.dev coverage)
• Termless — headless terminal testing
• Terminfo.dev — terminal feature support tables

License

MIT