Too many unknown factors. You can try the federal or turbotax estimators.
https://www.irs.gov/individuals/tax-withholding-estimator
TaxCaster tax calculator
Assuming you are single with $250,000 capital gains, some of the gain will be taxed at 15% and some at 20%. But the gain may also adjust the taxability of your social security.
Most states don't have a preferential capital gains rate and your gain will be taxed as ordinary income. State taxes range from 3% to 13% depending on the state.
