Work out how much money you need before you can stop working, and what age you'll get there. Tell it what you spend, what you save each month, and where you keep it — every term is explained as you go. Runs entirely in your browser; nothing you type is ever uploaded.

A three-step planner. Choose whether you're growing a monthly habit or funding a specific goal (with presets for a house, education or a car), enter the amount, horizon and return, then see what it becomes — total invested versus growth, the value in today's money, a growth chart and a year-by-year table you can export.

Once you've stopped working, will your savings last? Put in what you have and what you spend, and find out whether it holds out — or the age it would run dry. It also shows the most you could safely spend, and how much you'd need saved to afford the life you actually want.

See what a loan really costs. Put in how much you're borrowing, the interest rate and how long you'll take — and find out what you pay each month, how much extra the bank keeps, and how it changes year by year.

See what prepaying a loan actually saves. Add an extra amount each month or a one-off lump sum and compare the interest paid and the years knocked off.

Leave money with a bank and it pays you a little each year. See what you'd end up with — and whether it actually beats rising prices.

Three quick answers: how fast an investment really grew, what today's money will be worth later, and how much you should keep aside for emergencies.