The brand. The state. What incentives are taxable/not taxable.
This could be texas, or since @volvo1 guessed a Bolt, it could also be NY or NJ.
You are asking for helping getting your numbers to match. Instead, why don’t you spend a couple mins reading about corner cases of how the calculator arrives at the one pay numbers, and maybe that will help you understand what we’re asking and why (feel free to scroll up or down, but that is good a start as any):
It’s not perfect, but it’s very very close, and it accounts for a lot. Without all the inputs broken out, or a link to the calculator you are looking at, it’s impossible to answer with what you have provided.
Are you inputting the base mf into the calculator and then hitting one pay or are you inputting the one pay mf into the calculator and then hitting one pay?