May I recommend http://taxplancalculator.com/ ? It takes in to account state taxes, which potentially can make a difference between a tax cut and a tax hike. It also shows you an estimate of your federal taxes under the current laws, so that you can ascertain its precision against last years returns.
Its author, Maxim Lott, is a journalist and has been tweaking the calculations over the past couple of weeks reflecting the latest changes in the bills. You may have seen his predictive markets analysis site [1] in the run up to 2016 US Presidential Election.
As a matter of disclosure, the author is a friend and I helped him debug a couple of small issues.