Your data should be in a spreadsheet format, either as tab delinited (example) or comma seperated variables (example) file. In the spreadsheet, the data should be organized as follows: Each pair of columns should contain the measurements from one experiment, i.e. the measurements obtained on the wildtype or a mutant. The first column should specify the denaturant concentration, the second column should specify the observed folding rate (not the log folding rate) at the corresponding denaturant concentration. These data do not have to be in any particular order (i.e. it is not necessary to sort them for example by denaturant concentration). The pairs of columns from the different proteins, specifying the points to which the chevron curve is fit, should be stacked side by side. As the number of measurements can differ between experiments, the spreadsheet can contain empty cells (and these cells should be left empty, no funky characters or 9999s, please). Before uploading, please open your file in Excel or some comparable tool to make sure that the columns are properly aligned, i.e. that there are no extra tabs or commas (a text editor or note pad would not necessarily show extra tabs). The first row in the spread sheet may contain the identifiers of your mutants. Specifically, the names in the denaturant concentration columns (# 1, 3, 5, etc) will be used to identify the kinetic parameters and the Φ-values in the output generated (the names in columns # 2, 4, 6, etc are ignored). If no identifiers are given, the output will use capital letters starting with A for the first chevron. Before uploading, open your file in Excel or some comparable tool to make sure the columns