XLfit is an add-in for your Microsoft Excel. It analyze curve-fitting data with extensive selection of data analysis and calculation tools, including a superior range of fit and statistics models as well as charts and graphs to visualize, interpret and present experimental data, all in Excel. XLfit works within the familiar Excel spreadsheet environment to enable curve fitting and statistical analysis. At the heart of XLfit is a powerful curve-fitting engine that allows linear and non-linear curve fits, smoothing, statistics, weighting and error bars. XLfit allows rapid analysis of data and generation of crucial information about a fit, including 2D and 3D graphical representation and full statistical analysis.