Fuel Cost Calculator

Calculate the total cost to fill your vehicle’s gas tank and determine your exact cost per mile and cost per 100 miles driven. Note that US gallons (3

Automotive

Fuel Tank Capacity / Volume

gallons

Fuel tank capacity or volume purchased in US gallons.

Fuel Price (per gallon)

$/gal

Current price of fuel per gallon.

Vehicle Fuel Economy

MPG (US)

Average fuel economy in miles per US gallon.

Currency Symbol

Select preferred currency display symbol.

Formula & Methodology

Fill-Up Cost = Tank Capacity (gal) × Fuel Price ($/gal) | Cost per Mile = Fuel Price ÷ MPG

Total fill-up expense is the product of tank capacity in US gallons and the price per gallon. Dividing fuel price per gallon by your vehicle’s miles per gallon yields cost per mile. Multiplying cost per mile by 100 yields the standard 100-mile operational baseline. Estimated full-tank driving range is calculated as Tank Capacity × MPG.

Total Fill-Up Cost

51.1 $

Overview

Calculate the total cost to fill your vehicle’s gas tank and determine your exact cost per mile and cost per 100 miles driven. Note that US gallons (3.785 L) and UK imperial gallons (4.546 L) differ by 20%. Fuel prices fluctuate continuously, and driving range depends directly on vehicle speed, ambient weather, and traffic conditions.

Worked Examples

14.0 Gallon Tank at $3.65/gal (28.0 MPG)

Tank capacity 14.0 US gallons, fuel price $3.65 per gallon, vehicle economy 28.0 MPG.

Calculate total fill-up cost: 14.0 gal × $3.65/gal = $51.10.
Calculate total driving range: 14.0 gal × 28.0 MPG = 392 miles.
Calculate cost per mile: $3.65 ÷ 28.0 MPG = $0.130 per mile.
Calculate cost per 100 miles: $0.130 × 100 = $13.04.

Final Answer: Total Cost: $51.10 | Range: 392 miles | $0.130 / mile

18.0 Gallon SUV Tank at $3.80/gal (20.0 MPG)

Tank capacity 18.0 US gallons, fuel price $3.80 per gallon, vehicle economy 20.0 MPG.

Calculate total fill-up cost: 18.0 gal × $3.80/gal = $68.40.
Calculate total driving range: 18.0 gal × 20.0 MPG = 360 miles.
Calculate cost per mile: $3.80 ÷ 20.0 MPG = $0.190 per mile.
Calculate cost per 100 miles: $0.190 × 100 = $19.00.

Final Answer: Total Cost: $68.40 | Range: 360 miles | $0.190 / mile

10.5 Gallon Compact Car at $3.50/gal (35.0 MPG)

Tank capacity 10.5 US gallons, fuel price $3.50 per gallon, vehicle economy 35.0 MPG.

Calculate total fill-up cost: 10.5 gal × $3.50/gal = $36.75.
Calculate driving range: 10.5 gal × 35.0 MPG = 367.5 miles.
Calculate cost per mile: $3.50 ÷ 35.0 MPG = $0.100 per mile.
Calculate cost per 100 miles: $0.100 × 100 = $10.00.

Final Answer: Total Cost: $36.75 | Range: 367.5 miles | $0.100 / mile

How to Use This Calculator

Check your owner’s manual for your vehicle’s fuel tank capacity in gallons.

Enter the current price per gallon at your local gas station.

Input your vehicle’s average fuel economy (MPG).

Select your preferred currency symbol ($ , £, or €).

Review total fill-up cost, cost per mile, and total estimated driving range.

Reference Table

Fuel Price ($/gal)	20 MPG Vehicle	25 MPG Vehicle	30 MPG Vehicle	35 MPG Vehicle
$3.00 / gal	$0.150 / mi ($15.00/100mi)	$0.120 / mi ($12.00/100mi)	$0.100 / mi ($10.00/100mi)	$0.086 / mi ($8.57/100mi)
$3.50 / gal	$0.175 / mi ($17.50/100mi)	$0.140 / mi ($14.00/100mi)	$0.117 / mi ($11.67/100mi)	$0.100 / mi ($10.00/100mi)
$4.00 / gal	$0.200 / mi ($20.00/100mi)	$0.160 / mi ($16.00/100mi)	$0.133 / mi ($13.33/100mi)	$0.114 / mi ($11.43/100mi)
$4.50 / gal	$0.225 / mi ($22.50/100mi)	$0.180 / mi ($18.00/100mi)	$0.150 / mi ($15.00/100mi)	$0.129 / mi ($12.86/100mi)

Frequently Asked Questions

How do I calculate fuel cost per mile?

Divide the cost per gallon by your vehicle’s miles per gallon. For example, if gas costs $3.50 per gallon and your car averages 28 MPG, your fuel cost is $3.50 ÷ 28 = $0.125 per mile.

Does running my gas tank near empty harm the vehicle?

Yes. Submerged electric fuel pumps rely on fuel in the tank for cooling and lubrication. Consistently driving with less than a quarter tank can cause the pump to overheat and draw in settled debris from the bottom of the tank.

What is the difference between US and UK gallons for fuel costs?

A US gallon contains 3.78541 litres, while a UK gallon contains 4.54609 litres. If fuel is priced in imperial gallons, comparing directly to US prices requires multiplying the US gallon price by 1.20095.

How much money does improving gas mileage by 5 MPG save?

The savings follow an inverse curve. Improving from 15 to 20 MPG over 15,000 miles saves 250 gallons (approx. $875 at $3.50/gal). However, improving from 35 to 40 MPG over the same distance saves only 54 gallons (approx. $189).

Why does premium gasoline cost more, and does it improve mileage?

Premium gasoline contains higher octane additives that prevent premature detonation (knocking) in high-compression or turbocharged engines. Putting premium in a vehicle designed for regular 87-octane does not increase MPG or power.