Which calculator do I need?
- A goal with a date: the savings calculator gives your time to reach it and the monthly deposit it takes. $25,000 at $500 a month and an example 4% APY takes 3 yrs 11 mos.
- Interest on a set amount: the interest calculator covers simple and compound interest by day, month, or year, including CDs.
- Long-term growth: the compound interest calculator shows how contributions and time build up, with the Rule of 72.
- Money in the market: the investment calculator adds fees and a simulated range, because market returns aren't steady.
- A result you already have: the ROI calculator gives total and annualized return, so you can compare investments held for different lengths of time.
- Buying power: the inflation calculator uses official CPI data back to 1913, checks old salaries, and projects future costs.
A sensible order to use them in
- If you're carrying high-rate debt, run the debt payoff calculator first. It's compounding against you.
- Set your short-term goals in the savings calculator.
- Project long-term money with the investment calculator, and read the range rather than the headline.
- Convert the result to today's dollars, then check how it fits with the retirement calculator.
The numbers that matter most here
- Fees. $500 a month at a steady example 7% for 30 years reaches $609,986. A 1% annual fee cuts that to $501,253.
- Inflation. At 2.5% a year, that $609,986 buys what $290,806 buys today. $100 from 2000 buys what about $193 buys in 2026, the latest year being an estimate.
- Compounding frequency. Daily rather than monthly adds only $17 on $10,000 at 5% over 10 years. Compare APY instead.
- Safety. FDIC insurance covers deposits up to $250,000 per depositor, per insured bank, per ownership category. It doesn't cover stocks, bonds, or mutual funds.
These tools are for education, and no return shown here is a prediction or a recommendation. The compound growth guide explains how these pieces fit together. For personal advice, look for a registered investment adviser or a tax professional.
More tools for saving and investing
- Safe money: the emergency fund calculator sets a target, the CD calculator shows what a term deposit earns, and the APY calculator converts between rates.
- Big goals: the college savings calculator plans for tuition, and the net worth calculator shows where you stand overall.
- Investing: the dividend calculator models income, the dollar-cost averaging calculator compares buying over time with a lump sum, and the bond yield calculator works out yield to maturity.
- The math itself: the present and future value calculator puts money from different dates on the same footing.
For a longer walk-through, read How compound growth really works.