Click or drag to resize
Evaluation and Licensing

GemBox.Spreadsheet works in two different modes:

  • Free mode - free of charge, limited to 5 worksheets and 150 rows per worksheet.

  • Professional mode - requires purchasing a license key, no limitations.

Both modes use the same GemBox.Spreadsheet DLL so there is no need to reinstall the component when switching modes.

The first thing to do when coding with GemBox.Spreadsheet is to instruct the component in which mode it will be used. This is accomplished by calling SpreadsheetInfoSetLicense(String) method with the specific license key parameter:

  • FREE-LIMITED-KEY, to use the component in Free mode,

  • the license key that you receive after purchasing GemBox.Spreadsheet, to use the component in Professional mode.

Important note Important

SpreadsheetInfo.SetLicense method must be called before using any other class from GemBox.Spreadsheet component.

Tip Tip

SpreadsheetInfo.SetLicense method can be called multiple times. What is important is that it is called with the same license key.

Ideally, it should be called at the startup of your application. For example, it can be called in a Main method, an application startup event or a static constructor of your main class.


You can evaluate GemBox.Spreadsheet free of charge and for an unlimited time period, just download the component, install it and use it in Free mode.

Free mode delivers the same performance and set of features as Professional mode, with the following limitations:

If you want to evaluate GemBox.Spreadsheet performance beyond the first 5 worksheets and 150 rows, then handle SpreadsheetInfoFreeLimitReached event and set the FreeLimitEventArgsFreeLimitReachedAction to FreeLimitReachedActionContinueAsTrial, as in this following code snippet:

// Set license key to use GemBox.Spreadsheet in a Free mode.

// Continue to use the component in a Trial mode when free limit is reached.
SpreadsheetInfo.FreeLimitReached += (sender, e) => e.FreeLimitReachedAction = FreeLimitReachedAction.ContinueAsTrial;

// Here goes your application specific code.

This option will enable you to read / write entire spreadsheet content, with the following limitation imposed on all cells after the first 5 worksheets or 150 rows per worksheet, whichever comes first:

  • When loading / saving a spreadsheet - approximately 5% of (randomly selected) cells will have their value replaced with string TRIAL.


If you have evaluated the component and are satisfied with it, you can purchase the license key to use the component in the Professional mode - without any limitations.

After purchase, the only thing you need to do is to replace FREE-LIMITED-KEY with your purchased license key in SpreadsheetInfoSetLicense(String) method call.

Note Note

There is no other installer or DLL for the Professional mode. You should continue to use the reference to existing GemBox.Spreadsheet DLL in your project when switching to Professional mode.

Professional mode also includes technical support with prompt bug fixes. For more information, see Technical Support.