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