ThreeDify XLCurvFit

Deployed as an add-in for Microsoft Excel, ThreeDify XLCurvFit allows you to fit thousands of curve equations to your Excel data right within Excel.

ThreeDify XLCurvFit is the simplest, most cost-effective, and robust tool available to anyone who wants to fit curve equations to their spreadsheet data without leaving Microsoft Excel.

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ThreeDify XLCurvFit is currently distributed as a licensable module in ThreeDify XLGrapher v6.0.2 which was released on Feb. 14, 2024Please note that:

  • 32-bit and 64-bit installers are now merged into a single installer which automatically detects the version of Excel installed on the client’s computer and installs the correct XLSurfFit version accordingly

For existing XLGrapher or XLSurfFit customers, please note the following:

  • XLCurvFit requires a separate license. There is no upgrade path from either of the above products.
Installation & License Activation
  • For Windows 7, 8, 10, 11 or Vista, XLGrapher can now be installed on both Administrator and Standard User accounts.
  • XLCurvFit does NOT support Windows XP or lower.
  • Uninstall the existing version of XLCurvFit, if any.
  • Download and run XLCurvFit installer.
  • If you are installing XLCurvFit on a Standard user account, the installer will ask you to enter an administrator’s user name and password. After successful installation, you will be automatically returned to your Standard User account.
  • Note that the installer only installs XLCurvFit for the user account currently logged in. If you wish to install XLCurvFit for all users on a single machine, repeat the above steps.
  • Start Excel as an Administrator. To do that, click Windows Start button, type Excel. Microsoft Excel xxxx shortcut shall show-up. Hold down Ctrl+Shift keys and then right mouse click on Microsoft Excel xxxx, choose Run as administrator to start Excel.
  • Under ThreeDify XLCurvFit add-in menu within Excel, select License Manager and then select “3D Graphing or SurfaceFit” as the module name, and then hit Activate button.
  • Copy and paste your XLCurvFit Product Key, aka License Key, provided by ThreeDify.
  • Restart Excel as usual and your XLCurvFit  license shall be activated.

Note that another way to start Excel as an Administrator at Step 1 above is to right mouse click on any Excel shortcut (from Windows Start menu most likely), choose Properties, switch to Compatibility tab and set “Run this program as an administrator” checkbox to “on”. If that is done, then you need to set this checkbox “off” before performing the last step above.