tty-table

A TypeScript-first terminal table renderer with a compatibility-oriented factory API.

Examples

See here for complete example list

To view all example output:

$ git clone https://github.com/tecfu/tty-table && cd tty-table && npm i
$ npm run view-examples

Terminal (Static)

examples/styles-and-formatting.js

Terminal (Streaming)

$ node examples/data/fake-stream.js | tty-table --format json --header examples/config/header.js

• See the built-in help for the terminal version of tty-table with:

$ tty-table -h

MCP server

Expose tty-table to MCP clients (Claude, IDE agents, Cursor, etc.) over stdio.

Client configuration

{
  "mcpServers": {
    "tty-table": {
      "command": "npx",
      "args": ["-y", "--package=tty-table", "tty-table-mcp"]
    }
  }
}

Tools

Tool	Description
render_table	Render data as an ASCII/Unicode terminal table. Accepts header, rows, and any tty-table options; returns the rendered table as text.

Arguments for render_table:

Name	Type	Required	Description
header	(string | {value, align?, width?})[]	no	Column definitions
rows	(unknown[] | Record<string, unknown>)[]	yes	Row data (arrays of cells, or objects keyed by column name)
options	object	no	Any tty-table option (e.g. width, borderStyle, align, compact)

Example tool call:

{
  "header": [{ "value": "name" }, { "value": "score", "align": "right" }],
  "rows": [["Ada", 100], ["Grace", 98]],
  "options": { "width": 40 }
}

Rendered result:

  ┌───────┬───────┐
  │ name  │ score │
  ├───────┼───────┤
  │  Ada  │   100 │
  ├───────┼───────┤
  │ Grace │    98 │
  └───────┴───────┘

Additional tools may be added in future releases under the same MCP server.

Browser & Browser Console

• View in Chrome or Chromium at http://localhost:8070/examples/browser-example.html using a dockerized apache instance:

  git clone https://github.com/tecfu/tty-table
  cd tty-table
  docker run -dit --name tty-table-in-browser -p 8070:80 -v "$PWD":/usr/local/apache2/htdocs/ httpd:2.4
  

• live demo (chrome only): jsfiddle

• live demo (chrome only): plnkr

• source: examples/browser-example.html

What's new in 6.0

• ANSI-safe display-width calculation and Unicode-aware wrapping/truncation.
• Typed column/table options and formatter context.
• ESM and CommonJS package exports.
• Modern Node.js LTS baseline (Node 22+; raised from 20+ when adopting smartwrap v4).
• A standalone browser bundle is produced for direct use from a browser console or <script> tag.
• Legacy Table(header, rows, footer, options) and Table(rows, options) construction remains supported.

Compatibility

Node.js

Current releases require Node.js 22 or newer. This is a breaking change from the Node 20 baseline used by early v6 releases (and from the v5 line, which supported older Node.js releases). The floor was raised to match smartwrap@4 / breakword@2.1.0. If your application must remain on Node 20, stay on a prior tty-table release until you can upgrade.

The published package provides both ESM and CommonJS entry points for Node.js. The CLI requires Node.js 22+ as well.

API

import Table from "tty-table"

const table = Table(
  [{ value: "name" }, { value: "score", align: "right" }],
  [
    { name: "Ada", score: 100 },
    { name: "Grace", score: 98 }
  ],
  { borderStyle: "solid" }
)

console.log(table.render())

Formatter context

New code can use the explicit context form:

const formatter = (value: unknown) => String(value).toUpperCase()

The compatibility callback signature is still accepted. New integrations should prefer a formatter that accepts the documented context object and avoid relying on dynamic this mutation.

Width semantics

Widths are measured in terminal display columns, not JavaScript string length. ANSI escape sequences are ignored for measurement; Unicode code points are counted using breakword.width() (Unicode 18.0.0 East Asian Width + UAX #51 Emoji_Presentation). Wrapping and truncation operate on the same display-width semantics.

Compared with older releases that used wcwidth, some symbols that were previously treated as 1 cell are now 2 cells (for example ⚡ U+26A1). Tables containing those characters may reflow slightly; measurement is now aligned with the same library used for wrapping.

Development

npm install
npm run typecheck
npm run build
npm test
npm run test:unit
npm run lint