There are obviously many factors that go into taxes while trying to determine how much should be taken out of your pay so that you don't end up paying the IRS more than is needed or getting too much $ back.
Be sure to change your W-4 withholding each year as tax rules change as this can add a little bit back into your pocket.
Also consider if any dependents have moved out, or if you refinanced your mortgage cause you insurance deduction could have changed. Pay close attention to self-employment taxes.
Taxes can be a burden, but if done right, can help position your finances in a positive way!