Most calculators seem to follow cost of ownership which is great for looking at the value of a depreciating asset, but not so good at determining monthly costs and how that compares with another car. Instead of justifying the total cost of the car over the period of ownership, we wanted to understand how the car fits into our budget.

This spreadsheet was instrumental in deciding that we could (I will be completing configuration and putting the $2500 non-refundable deposit down in a few days after shifting money around).

The spreadsheet will need to be copied and customized to you and your area since it accounts for things like interest, tax, insurance, and energy rates. Mostly this just involves changing numbers, but you may need to change the formula for taxes which is specific to NC.

Yet Another Model 3 Cost Calculator

That said, Teslanomics calculator is pretty good -- I found it after I had built this. It provides a bit less detailed view, but does offer similar information.

I estimate yearly costs up to five years with totals as well as yearly totals divided down to monthly values. In addition, you can put in equivalent values for an ICE vehicle to compare against and see yearly and monthly savings compared to that vehicle. I need a new car this year regardless of whether I got the Model 3, so I plugged in values from Edmunds for the a 2018 VW GTI Golf which is the car I might have purchased if we hadn't decided on the Model 3.

We found that costs are pretty much upfront and savings are seen starting the second year. From there the savings increase rather dramatically. Affording the Model 3 for us was about ensuring we could comfortably get over that initial year hump and help fund year 2 with the tax credit.