Introduction

Cellify is a lightweight, zero-dependency spreadsheet library for JavaScript and TypeScript. It provides a simple, intuitive API for creating, reading, and manipulating Excel (.xlsx) and CSV files.

Features

• Zero Dependencies - Only uses fflate for ZIP compression (~8KB)
• Full TypeScript Support - Written in TypeScript with complete type definitions
• Excel Import/Export - Read and write .xlsx files with full formatting support
• CSV Import/Export - Handle CSV files with configurable delimiters
• Rich Styling - Fonts, colors, borders, alignment, number formats
• Cell Operations - Merge cells, freeze panes, auto-filters
• Formulas - Preserve and create Excel formulas
• Accessibility - Built-in helpers for screen readers
• WASM Acceleration - Optional Rust/WebAssembly parser for 10-50x faster imports

Why Cellify?

Feature	Cellify	ExcelJS	SheetJS
Bundle Size	~8KB (+40KB WASM)	~1MB	~500KB
Dependencies	1 (fflate)	15+	0
TypeScript	Native	Yes	Partial
Styling	Full	Full	Limited
WASM Parser	Yes (10-50x faster)	No	No
Streaming	No	Yes	Yes

Cellify is perfect for:

• Client-side Excel generation - Small bundle, works in browsers
• Simple spreadsheet tasks - When you don't need streaming for huge files
• TypeScript projects - First-class type support

Quick Example

import { Workbook, workbookToXlsxBlob } from 'cellify';

// Create a workbook
const workbook = new Workbook();
const sheet = workbook.addSheet('Sales Report');

// Add headers with styling
sheet.cell(0, 0).value('Product').style({ font: { bold: true } });
sheet.cell(0, 1).value('Revenue').style({ font: { bold: true } });

// Add data
sheet.cell(1, 0).value('Widget A');
sheet.cell(1, 1).value(1500);

// Export to Excel
const blob = workbookToXlsxBlob(workbook);

Installation

npm install cellify

Ready to get started? Head to the Getting Started guide!