Number Duck

v3.2.0 [J237]

Copyright (C) 2012-2025, File Scribe

https://numberduck.com

🦆 About

Number Duck is a programming library for developers to read and write Microsoft Excel compatible spreadsheets from a variety of languages.

See NumberDuck.html for API details, or check the example folders.

🫶🏻 Compatability

NumberDuck has automated testing to maintain that every feature can be written and read from XLS files. The current priority is to extend that support to XLSX files.

Feature	XLSX Support
Font Styles	✅
Pictures	✅
Themes / Fill Patterns	❌
Charts	❌
Formulas	❌

🚧 Installation

Since Number Duck is delivered as source, you can just drop NumberDuck.cs into your project.

💾 Saving and Loading a Spreadsheet

Here is a simple example of writing to a spreadsheet, and then reading it back in.

using NumberDuck;

class Application
{
	static int Main(string[] args)
	{
		System.Console.Write("Simple Example\n");
		
		Workbook pWorkbook = new Workbook(Workbook.License.AGPL);
		Worksheet pWorksheet = pWorkbook.GetWorksheetByIndex(0);

		Cell pCell = pWorksheet.GetCellByAddress("A1");
		pCell.SetString("Totally cool spreadsheet!");

		pWorksheet.GetCell(1,1).SetFloat(3.1417f);

		pWorkbook.Save("SimpleExample.xls", Workbook.FileType.XLS);
		
		Workbook pWorkbookIn = new Workbook(Workbook.License.AGPL);
		if (pWorkbookIn.Load("SimpleExample.xls"))
		{
			Worksheet pWorksheetIn = pWorkbookIn.GetWorksheetByIndex(0);
			Cell pCellIn = pWorksheetIn.GetCell(0,0);
			System.Console.Write("Cell Contents: " + pCellIn.GetString() + "\n");
		}

		return 0;
	}
}

More how to code in the example folders above, or at https://numberduck.com/docs

👮 License

Number Duck is dual licensed as Open Source (AGPLv3) and commercial closed source.

Closed source licenses may be purchased from https://numberduck.com