Gas Cost Calculator USA 🇺🇸
Planning a road trip or want to know exactly what your daily commute costs in gas? Fuel Smarter calculates your exact fuel cost based on your car's real-world MPG, current US gas prices, your route, and how fast you drive — including a breakdown by road type and a speed comparison so you can see how much you'd save by easing off the gas.
Calculate your gas cost nowCurrent US gas prices — May 2026
US gas prices vary significantly by state — California typically runs $0.80-1.00 per gallon higher than the national average due to state taxes and cleaner fuel requirements, while states like Texas and Mississippi often have the cheapest prices. Our calculator uses the national average by default but you can edit the price field to match your local pump price.
How much does a typical US road trip cost in gas?
Based on the national average gas price of $3.50/gallon and a typical car achieving 28 MPG:
| Route | Distance | Gas cost (28 MPG) | Gas cost (35 MPG) |
|---|---|---|---|
| New York to Washington DC | 225 miles | ~$10.00 | ~$8.00 |
| Los Angeles to San Francisco | 380 miles | ~$16.90 | ~$13.50 |
| Chicago to Detroit | 280 miles | ~$12.50 | ~$10.00 |
| Miami to Orlando | 235 miles | ~$10.45 | ~$8.35 |
| Dallas to Houston | 240 miles | ~$10.70 | ~$8.55 |
| New York to Boston | 215 miles | ~$9.55 | ~$7.65 |
| Seattle to Portland | 175 miles | ~$7.80 | ~$6.25 |
| Las Vegas to Los Angeles | 270 miles | ~$12.00 | ~$9.60 |
Based on $3.50/gallon national average. Use our calculator for your specific vehicle and local gas price.
How speed affects your gas costs in the US
The 65 mph sweet spot: Most American cars get their best highway fuel economy between 55-65 mph. Driving at 75 mph instead of 65 mph typically reduces fuel economy by 10-15%, adding $5-10 to a 300-mile trip.
Interstate speed limits vary by state — typically 65-80 mph. States like Texas allow 85 mph on some toll roads. Our calculator sets the default to 65 mph but you can adjust to match your typical interstate speed.
Cruise control saves gas. Maintaining a steady speed on highways is more efficient than constant small speed changes. Studies suggest cruise control can improve fuel economy by 7-14% on flat terrain.