Comparing Investments This calculator compares the net gain of a taxable investment versus a tax-favored one. You are viewing this website at a small screen resolution which doesn't support calculators. Click here to view this calculator. Share | Related Content Home Mortgage Deduction Use this calculator to assess the potential benefits of a home mortgage deduction. Red Flags for Tax Auditors Here are six flags that may make your tax return prime for an IRS audit. Capital Gains Tax Estimator Use this calculator to estimate your capital gains tax.