How the standard mileage deduction works
If you use your own car for business, you can deduct business miles x the IRS standard mileage rate instead of tracking actual vehicle costs. Commuting between home and a regular workplace does not count. Parking fees and tolls for business trips are deductible on top of the mileage rate.
The IRS publishes the rate on its standard mileage rates page and usually updates it each January; in 2026 it changed on July 1. The rates in the calculator are editable, and this page is re-checked each January.