As others have said, if this was the sale of your primary residence, and you meet the two year rule, there is no income tax on the capital gain. You do not even report it on your tax return, unless you got a form 1099-S. Selling due to divorce is an exception to the 2 year rule. You are allowed a reduced maximum exclusion.
For an estimate, Try this tool https://turbotax.intuit.com/tax-tools/calculators/taxcaster/?s=1. Enter your regular income first to see the regular tax. Then add the sale to see the effect.
Enter the difference between the sale price and what you paid for it originally as a long term capital gain (LTCG). Depending on how much total income you have LTCG are partially taxed at 0%, 15%, 20% and/or 23.8%.
