Method
How the maths works
Simple formulas, clear assumptions, nothing hidden.
1Set the inputs2Read the result3Sanity-check
How reliable are the results?
They use standard formulas on approximate inputs — good for planning, not for a final commitment.
Where does the data come from?
Country prices, pay and fuel figures are approximate 2026 estimates, set by hand.
Do I need an account?
No. Every calculation runs in your browser and works offline.
How many calculators?
10 calculators, each with 50 country variants, in two languages.
Calculators
Rent vs Buy
When does buying beat renting?
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Petrol vs EV
What an electric car really saves
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Solar Payback
Years until rooftop solar pays for itself
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Degree ROI
Does the degree pay for itself?
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Salary to Savings
How much is left, and when you reach a goal
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Car Loan vs Cash
Finance the car or pay cash and invest?
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Retirement Savings
Will the pot last, and what monthly income?
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Energy Bill Cut
What an efficiency upgrade saves
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Commute Cost
Cheapest way to get to work
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House Affordability
How much home can the income carry?
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