Find your true monthly and yearly commuting cost based on your round-trip distance and fuel efficiency.
Your daily commute adds up fast - this calculator multiplies your round-trip distance by your work days per month to find your true monthly and yearly fuel spend.
Monthly Cost = (One-Way Distance × 2 × Work Days) ÷ MPG × Gas Price
A 15-mile one-way commute at 28 mpg, $3.50/gallon gas, and 21 work days a month costs about $78.75/month, or roughly $945/year.
It multiplies your per-trip cost (fuel, tolls, or transit fare) by trips per day and working days per month.
Fuel is the obvious one, but parking, tolls, and a portion of maintenance/depreciation from the extra mileage all add to the true cost.
By putting different commute methods (driving vs transit vs biking) into the same monthly-cost terms, it's easier to compare beyond just travel time.