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Discover the power of SlapKit.Excel - the .NET library for building applications with native support for Microsoft Excel files (.xlsx, .xlsm). You can create documents from the ground up, or tweak existing ones, whithout any third-party dependencies. With it, you can do Excel tasks utilizing our easy-to-use API.

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No External Dependencies

SlapKit.Excel lets you work with Excel documents without needing Microsoft Excel, Microsoft Office, or any other software on your computer or server. It's a standalone tool that doesn't depend on external libraries or interfaces.


ClosedXML Full API Compatibility

SlapKit.Excel offers complete API compatibility with the popular ClosedXML library while adding a lot of new features, making it an ideal choice for existing ClosedXML users looking to enhance their Excel projects.


Create Excel documents from scratch or modify existing ones

Workbooks, also known as spreadsheet documents, are made up of one or more worksheets containing the cells for data entry. SlapKit.Excel provides a user-friendly API that lets you easily create new workbooks and worksheets, or modify existing ones. You can set themes, add charts, protect data, manage rows and columns, and import bulk data with ease.


SlapKit.Excel makes it easy to add and manage charts in your spreadsheets, helping you present data clearly with the right type of chart. Whether adding, removing, or adjusting charts, SlapKit.Excel provides straightforward tools for better data visualization.



A sparkline in SlapKit.Excel is a compact, in-cell chart that offers a visual snapshot of data trends. Ideal for depicting variations like seasonal fluctuations, economic cycles, or pinpointing peak and trough values, sparklines efficiently encapsulate key data trends within a series, directly within your worksheet cells.



Excel tables are designed for streamlined management and analysis of related data, and is becomes even more accessible with SlapKit.Excel. You can effortlessly create, modify, and style tables, enhancing both data organization and presentation.


Pivot Tables

A Pivot Table in Excel is an advanced feature designed for efficiently summarizing, analyzing, exploring, and presenting substantial volumes of data.


Number Formatting

You can enhance your data representation by allowing detailed formatting of numeric values in cells for things like currency, percentages, decimals, dates, phone numbers, or postal codes. SlapKit.Excel comes equipped with an array of pre-defined number formats, which you can use directly or modify to create custom formats tailored to your needs.



Easily insert formulas or equations for data analysis and processing in a single cell or a range of cells using SlapKit.Excel. With its 181 predefined functions, you can enhance your Excel tasks and bring more depth to your data handling.


Workbook protection

Protect the integrity of your Excel workbook to keep hidden worksheets private, and to restrict the addition, movement, deletion, hiding, or renaming of worksheets.


Worksheet protection

Worksheet protection is designed to safeguard your Excel worksheet against accidental or intentional modifications. This level of protection allows you to restrict editability to specified areas, ensuring the rest of the worksheet remains unaltered by users.


Hyperlinks in Excel are convenient for swiftly guiding users to specific sections of the workbook, opening local files, or accessing website addresses. With SlapKit.Excel, you can effortlessly add, delete, modify, and locate hyperlinks within your workbook's worksheets.



The grouping feature in SlapKit.Excel enables you to organize rows and/or columns into expandable and collapsible sections. This is particularly useful for simplifying detailed data presentation by showing only summaries while still keeping the full data accessible for users who wish to delve deeper.


Pictures (Images)

Pictures can greatly enhance your worksheets adding vibrant visuals and making it easier to interpret and derive insights from your data. SlapKit.Excel simplifies the process of adding, adjusting, and working with images, allowing for a more engaging and informative presentation of your content.



The sorting feature in SlapKit.Excel lets you effortlessly create and adjust sorting rules within worksheets, applying these rules to specific segments of your spreadsheet. This functionality offers the versatility to arrange data either horizontally by rows or vertically by columns, adjusting data organization and analysis to your specific needs.


Filtering (Autofilter)

The AutoFilter feature in Excel helps you easily search and organize your data. You can use it to show or hide specific values in one or more columns. When you apply a filter, rows that don't match your criteria will be hidden. This is useful for both text and numbers, and you can even filter by cell color. You can set up AutoFilter for your whole worksheet or just for a particular table, making it a flexible tool for managing your data.


Named Ranges

Named ranges in SlapKit.Excel refer to specific cell collections that can be quickly accessed via a designated name. This is particularly handy when you need to repeatedly reference the same cell range or provide users with easy access to a predefined cell area for use in formulas. Named ranges can be effectively utilized at both the workbook and worksheet levels, enhancing ease of use and efficiency.

Cell Styling

SlapKit.Excel offers a wide array of formatting capabilities, enabling you to tailor the appearance of cells with options like number formatting, font properties, border styles, color schemes, text alignment and orientation. These customizations can be applied not just to individual cells, but across entire cell ranges for cohesive and impactful visual presentations.


A "theme" in Excel encompasses a set of pre-defined design elements that can be uniformly applied to various components like workbooks, worksheets, charts, and more. Each theme is a cohesive blend of colors, fonts, and effects, designed to give your workbooks a consistent and professional appearance.


Merge cells

With SlapKit.Excel, you can easily merge two or more adjacent cells into one larger cell that extends across multiple rows and columns, creating a unified cell space.


Freeze Panes

The freeze panes feature in SlapKit.Excel is useful for keeping a portion of your worksheet constantly visible while scrolling through other parts. The API provides the flexibility to freeze any number of rows and columns as needed, ensuring crucial data remains in view.


Data Validation

Data validation in SlapKit.Excel provides you with the ability to control the types of data or values that users can input into a cell. You have the flexibility to set various data validation rules, whether it's specifying required values, creating drop-down lists, restricting entries to numbers or dates, limiting text length, or defining custom value criteria. This feature ensures data consistency and accuracy in your worksheets.


Document Properties

Document properties, commonly referred to as metadata, provide essential information about a file, helping to describe and identify it. These details typically include elements like the document's title, the author's name, the subject matter, and relevant keywords that encapsulate the document's themes or contents.


* Microsoft, .NET and Excel are trademarks of the Microsoft group of companies.