Fuel and mileage calculators
Each one does a single job and answers as you type. Nothing you enter leaves the page.
Gas mileage calculator
Two odometer readings and the gallons you put in. Your real MPG.
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Gas calculator
What a trip costs in fuel, and what each passenger owes.
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Cost per mile calculator
Fuel plus insurance, tyres and depreciation, per mile.
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MPG to L/100km converter
US MPG, UK MPG, L/100 km and km/L, all at once from one number.
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Mileage reimbursement calculator
IRS 2026 rates, both halves of the year, and whether the check covers your gas.
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Annual mileage calculator
Two odometer readings in, miles per year out, checked against your lease.
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MPG to km/L converter
Kilometres per litre from MPG and back, for Japan, India and Latin America.
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The calculators answer one question once. If you want the answer for your own car every week without typing anything in, that is what the app is for: log the fill-up, and MPG, cost per mile and monthly spend update on their own.
The calculator is the one-off. The app is the habit.
A calculator tells you what one tank did. Log every fill-up and you get the trend: the month your MPG dropped, the station that is quietly more expensive, and what the car really costs you per mile.
- → Odometer, gallons, price. That is the whole form.
- → MPG per tank and a running average, calculated the tank-to-tank way
- → Charts for MPG, monthly spend and the price you have been paying per gallon
- → Several vehicles, and a CSV export when the accountant asks
Free on the App Store. Android version in the works.
Last tank
28.4 MPG
Average
26.9
Cost per mile
$0.13
This month
$187
Fill-ups
42