simple-xlsx-export

A zero-dependency JavaScript/TypeScript library for exporting data to XLSX (Excel) files. No external libraries required - generates valid Excel files easily - for example as export from grids in applications, where no heavy libraries are needed.

Features

Zero Dependencies - No external libraries required
Small Bundle Size - Lightweight implementation
Simple API - Just two functions to export data
Security - Protection against formula injection and common vulnerabilities

Installation

npm install simple-xlsx-export

Quick Start

Recommended: Use exportFull() for Most Cases

For any data with numbers, dates, or when you want column widths, use exportFull(). It auto-detects types and is the easiest option!

import { exportFull, saveToFile } from 'simple-xlsx-export';

const data = [
  [
    { data: 'Name', width: 20 },
    { data: 'Age', width: 10 },
    { data: 'Salary', width: 15 }
  ],
  [
    { data: 'John Doe' },
    { data: 30 },        // Auto-detected as number!
    { data: 75000 }      // Works in Excel formulas!
  ],
  [
    { data: 'Jane Smith' },
    { data: 25 },
    { data: 65000 }
  ]
];

const xlsxData = exportFull(data, 'employees');
await saveToFile(xlsxData, 'employees.xlsx');

Alternative: exportOnlyString() for Text-Only Data

Only use this if you have pure text data with no numbers or dates:

import { exportOnlyString, saveToFile } from 'simple-xlsx-export';

const data = [
  ['Name', 'City', 'Country'],
  ['John Doe', 'New York', 'USA'],
  ['Jane Smith', 'London', 'UK']
];

const xlsxData = exportOnlyString(data, 'addresses');
await saveToFile(xlsxData, 'addresses.xlsx');

// Note: All values become text in Excel, even if they look like numbers

Key Differences

| Feature | exportOnlyString | exportFull | |---------|------------------|------------| | Input | string[][] | CellData[][] | | Type detection | ❌ All text | ✅ Automatic! | | Numbers work in formulas | ❌ No | ✅ Yes | | Column widths | ❌ No | ✅ Yes | | Best for | Pure text | Everything else |

All Supported Data Types Example

import { exportFull, saveToFile } from 'simple-xlsx-export';

const data = [
  [
    { data: 'Name', width: 20 },
    { data: 'Age', width: 10 },
    { data: 'Salary', width: 15 },
    { data: 'Start Date', width: 15 },
    { data: 'Active', width: 10 }
  ],
  [
    { data: 'John Doe' },              // string (auto)
    { data: 30 },                      // number (auto)
    { data: 75000 },                   // number (auto)
    { data: new Date('2020-01-15') },  // date (auto)
    { data: true }                     // boolean (auto)
  ]
];

const xlsxData = exportFull(data, 'employees');
await saveToFile(xlsxData, 'employees.xlsx');

// Explicit types (optional - auto-detection usually works)
const explicitTypes = [[
  { data: '100', type: 'string' },  // Force as text
  { data: '200', type: 'number' }   // Force as number
]];

API Reference

exportOnlyString(data, filename, sheetName?)

Exports a simple 2D array of strings to XLSX format. All values become text in Excel.

Parameters:

• data: string[][] - Two-dimensional array of strings
• filename: string - Output filename (without .xlsx extension)
• sheetName?: string - Optional sheet name (default: 'Sheet1')

Returns: Uint8Array - The XLSX file data

exportFull(data, filename, sheetName?)

Exports a 2D array of CellData objects with auto-type detection and formatting (recommended).

Parameters:

• data: CellData[][] - Two-dimensional array of CellData objects
• filename: string - Output filename (without .xlsx extension)
• sheetName?: string - Optional sheet name (default: 'Sheet1')

Returns: Uint8Array - The XLSX file data

saveToFile(xlsxData, filename)

Saves XLSX data to a file (Node.js only).

Parameters:

• xlsxData: Uint8Array - The XLSX file data from export functions
• filename: string - Output filename (will add .xlsx if missing)

Returns: Promise<void>

downloadInBrowser(xlsxData, filename)

Triggers a download in the browser.

Parameters:

• xlsxData: Uint8Array - The XLSX file data from export functions
• filename: string - Download filename (will add .xlsx if missing)

CellData Interface

interface CellData {
  data: string | number | boolean | Date;
  type?: 'string' | 'number' | 'boolean' | 'date';  // Auto-detected if omitted
  width?: number;  // Column width in character units (0-255)
}

Supported Data Types

• string - Text data
• number - Numeric values
• boolean - TRUE/FALSE values
• date - Date objects (formatted as dates in Excel)

Browser Usage

Requires a bundler (Vite, Webpack, Parcel, etc.)

import { exportFull, downloadInBrowser } from 'simple-xlsx-export';

// In your click handler
const xlsx = exportFull(data, 'report');
downloadInBrowser(xlsx, 'report.xlsx');

See QUICKSTART.md for React and other framework examples.

Security

Built-in protection against common vulnerabilities:

• Formula Injection Prevention - Automatically sanitizes dangerous formulas
• Input Validation - Enforces Excel's limits (1,048,576 rows, 16,384 columns)
• XML Escaping - Properly escapes all user data
• No Dependencies - Zero supply chain attack surface

Why Zero Dependencies?

• Smaller bundle - No bloat (~17 kB)
• Better security - No supply chain vulnerabilities
• Easier maintenance - No dependency updates needed
• Full control - Complete understanding of the codebase

Compatibility

Node.js: 14+
Browsers: All modern browsers (Chrome, Firefox, Safari, Edge)

License

MIT License - see LICENSE file for details.

Contributing

Contributions welcome! Read CONTRIBUTING.md first.

Core principles: Zero dependencies, extreme simplicity, small package size.

Repository

GitHub: simple-xlsx-export

Simple, focused XLSX export. That's it.