I've been able to find a UK tax calculator and of course a US tax calculator but I am unable to find a tax calculator on the internet that does both simultaneously (e.g., does a simple calculation of your UK taxes based on some basic checkboxes (married, etc.) and then also calculates what else you then owe the IRS given various exclusions and foreign tax credits. Does anyone know of one? Nothing comes up when I google it. Maybe there isn't one but it seems like there should be (just a generalized one based on some standard assumpitons and the exclusion rules, foreign tax credit rules in place at present).