Divide your total fuel expenses by the total miles you drive — for example, $1,600 spent on 15,000 miles equals 10.7¢ per mile.
What’s the actual cost of fuel per mile?
In 2026, the average U.S. driver shells out about 14–16 cents per mile for fuel, though hybrids can dip to 10¢ while big SUVs and trucks push past 20¢.
Take a typical sedan getting 25–30 mpg with gas at $3.50 per gallon — that lands you around 12–14 cents per mile. Your state’s gas taxes and fuel blends make a real difference here. Want an exact number? Track your fuel purchases over 1,000 miles, then divide total spending by total miles. Honestly, this is the most reliable way to know what you’re really paying. If you're curious about how this compares to other cost calculations, check out our guide on how to calculate PMF.
How do you actually calculate fuel cost?
Divide the trip distance by your car’s mpg, then multiply by the current gas price — for a 300-mile trip in a 25 mpg car at $3.50/gal, the cost is (300 ÷ 25) × 3.50 = $42.
Check your car’s window sticker or owner’s manual for real mpg figures. Electric or hybrid owners should use kWh per mile or miles per kWh instead. Mixed driving? Track your actual mpg over a month. Apps like Fuelly or your car’s built-in trip computer can do the heavy lifting for you. For more on calculating costs beyond fuel, see our breakdown of how to calculate rent per square feet.
How do you figure out how much petrol you burn per mile?
Record how many litres you add and the miles driven between fill-ups, then divide miles by litres — 300 miles ÷ 20 litres = 15 miles per litre.
Start with a full tank and reset your trip odometer. Fill up again when empty, note the litres added, and repeat at least twice. Most modern cars even show litres per 100 km on the dashboard. This little trick makes comparing fuel efficiency across different cars a breeze. If you're also curious about how pressure relates to calculations, read our guide on how to calculate area with pressure and force.
What’s the best way to calculate cost per mile?
Divide total expenses (fuel, tolls, wear) by the miles you drive — $42 spent on a 300-mile trip equals 14¢ per mile.
For a full picture, toss in fixed costs like insurance and depreciation, then divide by your annual miles. AAA’s Your Driving Costs report has solid averages by vehicle type. For personal budgeting, track a full fuel cycle or use your car’s trip computer if it’s got one. To explore another type of engine calculation, check out how to calculate the compression ratio of a diesel engine.
How do I estimate petrol cost for a trip?
Divide the distance by your car’s mpg and multiply by the gas price — a 400-mile trip in a 30 mpg car at $3.60/gal costs about $48.
Add a 10–15% buffer for traffic, detours, or running low on gas. Check average gas prices for your route with apps like GasBuddy or AAA TripTik. Electric vehicle owners should multiply miles by kWh per mile and your current electricity rate. Always double-check prices before you hit the road. For insights on fuel types used in homes, see our article on which fuel is best used in homes.
What’s the cost to fill a 1-litre tank?
Filling a 1-litre tank usually costs $1–$3 depending on local prices, since most stations let you fill any amount — expect to spend around $2 for a full tank at $2.00 per litre.
(Most pumps allow fills over $1–$2, so you can top up even a few litres.) A 50-litre tank at $1.80/litre, for instance, costs $90 to fill. Check your car’s manual for minimum fill tips, though most modern cars handle partial fills just fine. If you need help with fuel system maintenance, read our guide on how to bleed air out of a fuel line.
How do you convert 30 mpg to miles per litre?
30 miles per gallon equals about 12.75 kilometres per litre or 7.84 litres per 100 km — handy for comparing fuel efficiency across different systems.
Here’s how: 1 US gallon = 3.785 litres, so 30 mpg = 30 miles ÷ 3.785 litres = 7.93 miles per litre. In Canada and most of the world, fuel economy is shown as L/100 km, so 30 mpg is roughly 7.8 L/100 km. Use this to compare vehicles from different markets. For more on atmospheric calculations, visit our page on how to calculate atmospheric pressure.
How do I find my car’s fuel tank size?
Small to midsize cars usually have 12–18 gallon tanks; SUVs and trucks range from 20–30 gallons — a 2026 Honda Civic typically has a 14.8-gallon tank.
Your owner’s manual or a quick lookup on Edmunds or Kelley Blue Book will give you the exact figure. For a rough estimate, measure the tank’s length, width, and height in inches, multiply them, then divide by 231 (cubic inches per gallon). Just remember the real capacity is slightly less due to unusable fuel. If you're curious about fuel-injected systems, check out whether the 2011 CRF 450R is fuel injected.
Is a 1-litre car worth it?
A 1-litre engine shines in city driving, delivering 40–50 mpg and keeping running costs low — perfect for short trips, stop-and-go traffic, and budget-focused commuters.
That said, it might struggle to merge on highways or tow anything heavy. These engines are common in European and Asian models like the Toyota Yaris or Hyundai i20. Think about your driving habits — 1-litre cars are great in the city but can feel underpowered on long highway drives. For insights on alternative fuels, see our article on where biomass fuel is used.
What’s the best speed to maximize distance with 1 litre of fuel?
For the best fuel efficiency with 1 litre, cruise at 50–55 mph (80–90 km/h), where drag and engine load balance out — speeds above 60 mph start eating into your range.
Eco-driving helps too — accelerate gently, keep throttle steady, and avoid idling. Cruise control works wonders on flat roads. Real-world factors like hills, wind, and tire pressure also play a role. Try testing your car’s sweet spot by tracking fuel economy over a few trips. You’ll usually find the sweet spot falls somewhere in that 50–55 mph range. For more on energy drinks and gaming performance, read our review of whether Gfuel is good for gaming.
