Calculators
Small tools that turn the ideas in the lessons into numbers you can try for yourself. Each one explains its formula and its limits. They run in your browser and nothing you type is stored or sent anywhere.
- Compound interest and SIP calculator
How much could my money grow with compounding?
See how a lump sum and regular monthly investments could grow at an assumed yearly return, with a year-by-year table and the formula explained.
- CAGR and percentage change calculator
How fast did something grow each year, on average?
Work out the percentage change and the compound annual growth rate (CAGR) between two values, and see why a simple yearly average overstates growth.
- Loss recovery calculator
What gain do I need to recover from a loss?
Find the percentage gain needed to recover from a loss, and roughly how long recovery takes at a steady return. A 50% loss needs a 100% gain.
- Share return calculator
How much did I really make or lose on a share?
Work out the total return on a share, including price change, dividends and costs, in rupees, as a percentage and as an annualised yearly return.
- P/E ratio calculator
How do I calculate a company's P/E ratio?
Calculate earnings per share, the price-to-earnings (P/E) ratio, earnings yield and market capitalisation from a share price, net profit and share count.
- Real return calculator
What is my return after inflation?
Find your real return after inflation, and what a future amount will buy in today's money. See why a 7% return with 6% inflation is barely 1% real.
- Position size and risk/reward calculator
How many shares can I hold so a stop-loss costs only what I planned?
Work out how many shares keep a loss at your stop to a fixed share of capital, with the reward-to-risk ratio and the win rate needed to break even.
- Leverage calculator
What does borrowing to invest do to my risk?
See how borrowed money magnifies gains and losses on your own money, including interest, and the price fall that would wipe out your investment.
- Option payoff calculator
Where does an option position make or lose money at expiry?
See the profit or loss at expiry of buying or selling calls and puts, alone or as a two-option spread, with breakevens and the maximum gain and loss.
- Guaranteed return reality check
Is a promised monthly return realistic?
Turn a promised monthly return into what it means per year and over five years. A "safe" 5% a month is about 80% a year, a sign of a scam.
These calculators illustrate how the arithmetic works. They are not forecasts, and they are not advice about what to buy or sell.