Federal Income Tax Use this calculator to estimate your income tax liability along with average and marginal tax rates. You are viewing this website at a small screen resolution which doesn't support calculators. Click here to view this calculator. Related Content What If You Get Audited? The chances of an IRS audit aren't that high. And being audited does not necessarily imply that the IRS suspects wrongdoing. Disability and Your Finances In the event of an unforeseen accident or illness, disability insurance may be a good way to protect your income and savings. Tax Freedom Day Assess how many days you'll work to pay your federal tax liability.