fmtable

Zero-dependency ASCII/Unicode table formatter for Node.js, Deno, and browsers.

Inspired by Python's tabulate and Go's tablewriter — now in pure TypeScript with no runtime dependencies.

╭────┬────────────────────┬────────────╮
│ ID │ Name               │ Downloads  │
├────┼────────────────────┼────────────┤
│  1 │ fmtable            │  1,200,000 │
│  2 │ cli-table3         │    900,000 │
│  3 │ tabulate (Python)  │  3,000,000 │
╰────┴────────────────────┴────────────╯

Features

• 6 border styles — plain, simple, grid, rounded, pipe (GitHub Markdown), minimal
• Per-column alignment — left, right, center
• Auto-width calculation — fits content, respects minWidths / maxWidths
• ANSI-aware — strips escape codes before measuring width
• CJK-aware — correct double-width character handling
• Row separators — optional separator between every data row
• Cell truncation — truncates overflowed cells with …
• CLI included — pipe JSON arrays straight from the shell

Install

npm install @billdaddy/fmtable

Usage

import { fmtable } from "@billdaddy/fmtable";

const table = fmtable(
  [
    [1, "Alice",  "Engineering"],
    [2, "Bob",    "Design"],
    [3, "Carol",  "Marketing"],
  ],
  {
    headers: ["ID", "Name", "Department"],
    style:   "rounded",              // default
    align:   ["right", "left", "left"],
    padding: 1,                      // default
  },
);

console.log(table);

Output:

╭────┬───────┬─────────────╮
│ ID │ Name  │ Department  │
├────┼───────┼─────────────┤
│  1 │ Alice │ Engineering │
│  2 │ Bob   │ Design      │
│  3 │ Carol │ Marketing   │
╰────┴───────┴─────────────╯

Styles

Name	Example
plain	whitespace-separated, no borders
simple	dashes as top/bottom/header separators
grid	+--+--+ box-drawing
rounded	╭──╮ Unicode rounded corners (default)
pipe	| --- | GitHub Markdown tables
minimal	│ column separators only

fmtable(rows, { style: "grid" });
// +---+-------+
// | 1 | Alice |
// +---+-------+
// | 2 | Bob   |
// +---+-------+

fmtable(rows, { style: "pipe", headers: ["ID", "Name"] });
// | ID | Name  |
// |----|-------|
// | 1  | Alice |
// | 2  | Bob   |

API

fmtable(rows, options?)

Parameter	Type	Default	Description
rows	CellValue[][]	—	2-D array of rows
options.headers	string[]	—	Column header labels
options.style	StyleName	"rounded"	Border style
options.align	Align | Align[]	"left"	Per-column or global alignment
options.padding	number	1	Spaces on each side of content
options.minWidths	number[]	[]	Minimum column widths
options.maxWidths	number[]	[]	Maximum column widths (truncates with …)
options.rowSeparators	boolean	false	Add separator between every row

CellValue is string | number | boolean | null | undefined.
Align is "left" | "right" | "center".
StyleName is "plain" | "simple" | "grid" | "rounded" | "pipe" | "minimal".

CLI

# Pipe a JSON array of row arrays
echo '[[1,"Alice","Engineering"],[2,"Bob","Design"]]' \
  | fmtable --headers ID,Name,Department --style grid

# Or from a file
cat data.json | fmtable --style pipe --align right,left,left

Options: --style, --headers, --align, --padding, --row-sep, --help.

vs. alternatives

Package	Zero-dep	TypeScript	Styles	CJK	ANSI	CLI
fmtable	✅	✅	6	✅	✅	✅
cli-table3	❌	partial	3	❌	✅	❌
table	❌	✅	1	❌	✅	❌
text-table	✅	❌	1	❌	❌	❌
columnify	✅	❌	1	❌	❌	❌

Contributors ✨

Contributions of any kind are welcome! See the contributing guide and add yourself via @all-contributors please add @<username> for <contributions>.

License

MIT © trananhtung