Skip to content

CALCULATOR · Finance

Compound Interest Calculator

See what compounding itself does to a balance — annual, monthly or daily — and what APY a nominal rate actually pays.

Show formula
FV = P(1+i)^N + PMT·(((1+i)^N−1)/i)

Method reviewed:Standard compound future-value formula FV = P(1 + r/n)^(nt) · reviewed August 2026

Inputs

Compounding frequency

—
—

Result

Your result appears here

Enter Loan amount and the result fills in as you type.

How it works

  1. Enter a starting balance and regular contribution.
  2. Set rate, duration and compounding frequency.
  3. Read final balance, interest earned and the growth curve.

Frequently asked questions

When are contributions added?

At the end of each compounding period — the standard ordinary-annuity assumption.

Is APY the same as APR?

No. APR is the nominal annual rate; APY includes the effect of intra-year compounding. The tool shows the effective APY next to your rate.

Is this financial advice?

No — it is pure arithmetic projection without taxes, fees or market risk.

Examples

10,000 at 5% for 10 years, compounded monthly
16,470.09, of which 6,470.09 is interest. Monthly compounding turns the 5% nominal rate into an effective 5.12% a year.
The same 10,000 compounded annually
16,288.95 — 181.14 less than with monthly compounding. Compounded daily it would reach 16,486.65.

Which of these should I use?

These four run the same future-value arithmetic. What separates them is the question you are asking, not the maths:

  • Savings Calculator — the money sits in a savings account at a rate the bank quotes you, and you want to know what a fixed monthly deposit turns into.
  • Investment Calculator — the return is an assumption rather than a promise, and you need the answer in today's money — inflation-adjusted value and effective CAGR alongside the raw total.
  • Retirement Calculator — the question is not the balance but the income it supports, at a withdrawal rate, on a date you name.

Related calculators