Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Future value
$18,194
Interest earned
$8,194
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter starting amount ($).
- 2Enter annual rate (%).
- 3Enter years (years).
- 4Enter compounding.
- 5Read your future value on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Project the future value of a starting balance compounded at a chosen frequency.
Worked example
Using the values the calculator loads with:
Inputs
- Starting amount: 10000 $
- Annual rate: 6 %
- Years: 10 years
- Compounding: Monthly
Results
- Future value: $18,193.97
- Interest earned: $8,193.97
What each field means
Inputs
- Starting amount ($)
- The starting amount used in the calculation, measured in $. Starts at 10000 $ so you have a working example on load.
- Annual rate (%)
- The annual rate used in the calculation, measured in %. Starts at 6 % so you have a working example on load.
- Years (years)
- The years used in the calculation, measured in years. Starts at 10 years so you have a working example on load. Accepted range: 0–80 years.
- Compounding
- Pick the option that matches your situation — the maths changes per option. Choices: Annually, Semi-annually, Quarterly, Monthly, Daily.
Results
- Future value
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Interest earned
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the compound interest calculator work?
Project the future value of a starting balance compounded at a chosen frequency. The underlying maths is: FV = P × (1 + r/n)^(n·t)
What do I need to enter?
4 values: starting amount, annual rate, years, and compounding. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the future value result mean?
It is returned as a money amount in US dollars and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Compound Interest Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/compound-interest
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/compound-interest" target="_blank" rel="noopener">Compound Interest Calculator — RevenueLab</a> (2026).</p>
Source: [Compound Interest Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/compound-interest) (2026).