Investing Calculators
Eleven calculators that answer the questions investors actually ask. Results update as you type, and nothing leaves your device.
Compound Growth Calculator
How much will regular investing grow to? Try changing the years: time is the most powerful input.
Position Size Calculator
Risk a fixed percentage of your account on each trade.
Risk/Reward Calculator
Is the potential gain worth the potential loss?
Average Cost Calculator
See your new break-even after buying more shares.
FIRE Number Calculator
The portfolio size that can fund your yearly spending.
Fair Value (P/E) Calculator
Project earnings forward, apply an exit P/E, discount back to today.
Inflation Calculator
What will today’s costs be in the future, and what is cash really worth?
Rule of 72
Divide 72 by the annual return to estimate years to double.
Dividend Income Calculator
Yield, income today, and income after a decade of dividend growth.
Profit / Loss Calculator
Net result of a trade after fees, plus your break-even price.
Loan Payment Calculator
Monthly payment and lifetime interest on a fixed-rate loan.
Live currency cross rates
LiveHow to get the most from these calculators
Use conservative assumptions. Long-run stock market returns have historically averaged high single digits before inflation, but no return is guaranteed and sequences of bad years happen. Run each scenario at a pessimistic, base and optimistic rate.
Risk first, reward second. Professional traders decide how much they are willing to lose before they think about upside. The position size and risk/reward calculators enforce that discipline. Our guide on risk management explains the maths.
Remember inflation and fees. A 7% nominal return with 3% inflation is roughly 4% in real purchasing power. A 1% annual fee can consume a large share of long-term gains. See compound interest and dollar-cost averaging.
Calculators are educational estimates, not financial advice, and do not account for taxes or your personal situation.