Gas Calculator

Calculate your trip fuel costs easily with our free online gas calculator. Support various fuel efficiency units and currencies. Perfect for road trips, daily commute and budget planning. Compare fuel economy between vehicles.

Trip Information

Fuel Efficiency Comparison Guide

Vehicle Type Typical Efficiency CO₂ per 100km
Compact Car 5-7 L/100km (33-47 MPG) 11.5-16.2 kg
Sedan 6-9 L/100km (26-39 MPG) 13.9-20.8 kg
SUV 8-12 L/100km (20-29 MPG) 18.5-27.7 kg
Truck 10-15 L/100km (16-24 MPG) 23.1-34.7 kg
Hybrid 4-6 L/100km (39-59 MPG) 9.2-13.9 kg
Electric Vehicle 15-20 kWh/100km 0 kg (tailpipe)
Motorcycle 3-5 L/100km (47-78 MPG) 6.9-11.5 kg

Money-Saving Tips

  • Maintain Proper Tire Pressure: Under-inflated tires can increase fuel consumption by up to 3%
  • Drive Smoothly: Avoid rapid acceleration and hard braking to improve efficiency by 10-40%
  • Reduce Weight: Remove unnecessary items from your vehicle; every 50kg adds about 2% to fuel consumption
  • Use Cruise Control: Maintains steady speed on highways, improving fuel economy
  • Plan Your Route: Avoid traffic jams and choose the most direct route to save fuel
  • Regular Maintenance: Keep up with oil changes, air filter replacements, and tune-ups
  • Limit Idling: Idling uses 1/4 to 1/2 gallon of fuel per hour with no mileage gained
  • Combine Trips: Plan multiple errands in one trip to avoid cold starts which use more fuel
Instant results No signup required Standard formulas Free to use

Frequently Asked Questions about Gas Calculator

How do I calculate gas cost for a round trip using this tool?

Simply enter the total round trip distance. If your trip is 150 miles each way, put 300 miles in the distance field. The calculator doesn’t assume one-way or round trip—it works with whatever number you provide. Many people forget to double the distance, so double-check before hitting calculate.

Does this gas cost estimator work with currencies other than USD?

Yes. The currency selector includes USD ($), Euro (€), British Pound (£), Chinese Yuan/Japanese Yen (¥), Indian Rupee (₹), Korean Won (₩), Russian Ruble (₽), and Brazilian Real (R$). The calculator treats these as display symbols only—it performs all math in pure numbers, so you can also type any currency symbol manually by leaving the selector on your local currency.

What’s the most fuel-efficient speed for reducing trip costs?

While the calculator doesn’t control your driving, the data shows that most cars achieve peak fuel economy between 50-65 mph (80-105 km/h). Above 65 mph, efficiency drops quickly. For every 5 mph you drive over 50 mph, it’s like paying an extra $0.20 per gallon. The calculator’s money-saving tips section covers this and seven other practical ways to reduce consumption without changing your route.

Can I use this on my phone without downloading an app?

Absolutely. The page works perfectly on mobile browsers. Just open it in Safari, Chrome, or Firefox on your phone. There’s no app to download, no signup required, and no storage space taken. This is a free online gas calculator with no download needed, which makes it ideal for checking costs while you’re already at the pump or sitting in a passenger seat planning a route.

How accurate is the CO₂ emissions estimate?

The calculator uses the standard industry average of 2.31 kg of CO₂ per liter of gasoline burned. For diesel, it would be slightly higher (around 2.68 kg/L). This is an estimate based on complete combustion. Your actual emissions may vary slightly based on driving conditions, fuel blend, and engine efficiency. That said, it’s accurate enough to compare the environmental impact between different trips or vehicles.

Why does the cost per mile change when I switch between L/100km and MPG?

That’s not a bug—it’s because L/100km and MPG measure opposite things. Lower L/100km means better efficiency. Higher MPG means better efficiency. When you toggle between them, the calculator converts the value so the underlying fuel consumption remains the same. The cost per mile should stay identical. If you see a change, double-check that you entered the correct numerical value for the unit you selected.