Collection
Investment calculators
Project what your money grows to, check what an investment actually returned, and plan the long game. Every calculator runs in your browser, opens with a worked example, and shows the formula behind the result.
Project growth
Start here when you know what you will put in and want to see where it ends up.
- Compound Interest CalculatorA lump sum plus regular contributions, at any compounding frequency.Finance
- CD CalculatorA certificate of deposit's value and interest earned at maturity.Finance
- Savings Goal CalculatorThe monthly deposit needed to reach a target by a set date.Finance
- Simple Interest CalculatorInterest on the principal only, as on many bonds and short-term notes.Finance
Measure returns
Use these after the fact, to see what an investment really earned.
- ROI CalculatorTotal and annualized return from what you paid and what it is worth now.Business
- Rule of 72 CalculatorA quick estimate of how many years money takes to double at a given rate.Finance
- Stock Average CalculatorYour average cost per share after buying at several prices.Finance
- Crypto Profit CalculatorProfit or loss on a crypto trade, including fees.Finance
Plan retirement
Long-horizon plans where contributions, employer match and time do most of the work.
- Retirement CalculatorWhether your savings and contributions reach the income you will need.Finance
- 401(k) CalculatorYour 401(k) balance at retirement, including the employer match.Finance
- Roth IRA CalculatorTax-free Roth IRA growth, with this year's contribution limit and income phase-out.Finance
- FIRE CalculatorThe portfolio needed to retire early, and how long it takes to get there.Finance
Keep score
Put growth in context: real purchasing power and the whole balance sheet.
Questions about investment calculators
- Which investment calculator should I start with?
- The compound interest calculator. Enter what you have now, what you will add each month, a rate of return and a number of years, and it shows the end balance and how much of it is growth rather than your own contributions.
- What rate of return should I enter?
- Try a range instead of a single number. Run the same plan at a cautious rate and an optimistic one to see how much the outcome depends on it. Past returns do not guarantee future ones, so treat every projection as an estimate.
- What is the difference between ROI and annualized return?
- ROI is the total gain divided by what you put in, regardless of how long it took. Annualized return converts that into a steady yearly rate, which lets you compare investments held for different lengths of time.
- Do these calculators include taxes and fees?
- They project growth before tax unless a calculator says otherwise. To account for fund fees, lower the rate of return by the annual expense ratio, for example 7% minus a 0.5% fee is 6.5%.