tty-table

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

Examples

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

Static

Terminal (Streaming)

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

Streaming

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

Browser Console Example

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 20+).
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

v6 requires Node.js 20 or newer. This is a breaking change from the v5 line, which supported older Node.js releases. If your application must remain on an older Node version, stay on the v5 release line.

The published package provides both ESM and CommonJS entry points for Node.js. The CLI requires Node.js 20+ 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; wide Unicode characters are counted using wcwidth. Wrapping and truncation operate on the same measurement primitive.

Development

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