I used a few calculators that are for the new tax laws. I drop a large amount into tax advantaged retirement accounts through work and am married with two kids.

Basically, with the amount I put into retirement accounts each month I had already overpaid my tax bill this year. So I stopped it.

There is also no longer a 15% bracket this year, there is a 10%, 12%, and then 22% etc. The standard deduction is now $12k each for the wife and I.