There are so many factors involved that there's no simple way to calculate the tax. (And you have not given any details that might narrow down the possibilities.) The best approach would probably be to prepare a "what-if" tax return using 2024 software. The results will be close enough for an estimate.
Unless the software tells you that you can exclude the entire capital gain from taxation, the amount of tax on the gain could depend on the amount of your other income. So in your what-if tax return you would have to enter all of your anticipated income for the year.
