Financial Calculators

Compound Interest Calculator

Project how a starting balance and recurring deposits may grow over time. Compare compounding frequencies and see principal, contributions and estimated earnings separately.

Recurring depositsCompounding optionsGrowth breakdown

Calculate compound growth

Compound Interest Calculator

Estimate how principal, recurring contributions, and compound growth change over time.

Growth assumptions

Contribution Timing

A monthly event simulation applies contributions at the selected period boundary and compound interest at the selected frequency.

Growth estimate

Ending Balance—
Starting Principal
—
Total Contributions
—
Interest / Growth Earned
—
Inflation-Adjusted Ending Balance
—
Effective Annual Rate
—
Total Investment Duration
—

Your calculation is processed in your browser and is not stored by this tool.

Balance composition and growth

  • Principal —
  • Contributions —
  • Growth —
Annual growth table
YearStarting BalanceContributionsInterest EarnedEnding Balance
Projection based on your assumptions

The entered figures remain in browser memory. A growth rate is an assumption, not a guaranteed investment return or savings-account offer.

How to use the compound interest calculator

  1. 1

    Enter the starting principal or current balance.

  2. 2

    Add an annual interest or return rate and the number of years.

  3. 3

    Select the compounding frequency used in your scenario.

  4. 4

    Enter an optional recurring contribution and its timing.

  5. 5

    Review the ending balance, total deposits and estimated compound earnings.

What compound interest means

Simple interest is calculated only on the original principal. Compound interest applies growth to principal and previously added interest. Over multiple periods, the growing base can produce growth on earlier growth. Time, rate, fees and contributions all affect the result.

Basic formula: A = P(1 + r/n)nt, where P is principal, r is the annual rate, n is the number of compounding periods per year and t is time in years. Recurring deposits require an additional cash-flow calculation.

Compound-growth example

Start with $10,000 and add $200 per month for ten years. Contributions add $24,000, so $34,000 of the final amount comes from deposited money. Any amount above that is modeled growth, subject to the entered rate and contribution timing.

Daily, monthly and annual compounding

More frequent compounding can increase the effective annual return when the stated nominal rate is the same. The difference may be small at moderate rates but becomes more visible over long periods. Compare frequencies only when the underlying product quotes the same type of rate.

Contributions and timing

Regular deposits often have a larger effect than a small change in compounding frequency. A contribution made at the beginning of a period has more time to grow than one made at the end. Keep timing consistent when comparing calculators or account projections.

Important limitations

  • Return: investments do not grow at a smooth fixed rate and can lose value.
  • Tax and fees: deductions can materially reduce net growth and are included only if modeled separately.
  • Inflation: a higher nominal balance does not always mean equal purchasing power.
  • Currency: the form uses its built-in currency symbol and does not convert exchange rates.

For a savings account, use the provider’s quoted rate and compounding rules. For an investment, compare several return assumptions rather than relying on one optimistic figure.

Annual contribution increases and inflation

If regular deposits are expected to rise with income, use the annual contribution-increase field to model that change. The inflation setting produces an adjusted ending balance for purchasing-power context. Both are assumptions, so test more than one rate.

Related tools

Savings CalculatorEstimate how regular deposits and interest may build toward a savings goal.Open tool →Retirement CalculatorProject retirement savings from current funds, salary, contributions, matching, growth and inflation.Open tool →ROI CalculatorCompare investment cost and gain using return, annualized return and break-even measures.Open tool →Inflation CalculatorCompare purchasing power across time using an entered inflation rate or price change.Open tool →

Compound Interest Calculator FAQ

How do I calculate compound interest?

Enter principal, annual rate, time and compounding frequency. Add recurring deposits if they are part of the scenario.

What is the difference between simple and compound interest?

Simple interest applies only to original principal. Compound interest also applies to accumulated interest from earlier periods.

Is daily compounding always better than monthly compounding?

At the same nominal rate it generally produces a slightly higher effective return, but fees, taxes and quoted-rate conventions can matter more.

Can I include monthly contributions?

Yes. Enter a recurring contribution so deposits and modeled growth appear separately.

Does the result include tax or inflation?

Not automatically unless the form offers and you enter those assumptions. Treat the displayed amount as a nominal projection.

Are compound-interest results guaranteed?

No. The tool applies the rate you enter mathematically. Actual investment returns and future account rates are uncertain.

Explore the complete Shopshubb Tools directory or return to Financial Calculators.

Scroll to Top
WhatsAppChat with Shopshubb