Pick two types of tissue culture vessels from the menus and the tool will calculate the surface area ratio. For a vessel not on the list, choose "Custom Vessel: Enter parameters manually". The surface area in cm2 can then be entered manually. After the surface area ratio is calculated, the desired cell dilution factor can be entered manually to generate the final dilution factor used to split your cells.
The calculated final dilution factor takes into account both the desired cell dilution factor and the difference in surface area of the source and target tissue culture vessels. Use this to dilute cells lifted from one vessel into another vessel. Surface areas given are of the total growth area available to cells and, in the case of a multi-well vessel, for a single well.