Continuous Compound Interest Calculator

Quick answer

The continuous compound interest calculator works out the future balance when interest compounds continuously – A = Pe^(rt) – plus regular deposits, and compares it with monthly compounding.

$
%
$
Final balance
$ —
Compound interest
$ —
Effective annual rate
— %
Same with monthly compounding
$ —

Continuous compounding is the mathematical limit of compounding more and more often. It gives the maximum possible growth for a given nominal rate, though in practice it is only slightly more than daily compounding.

How to use the Continuous Compound Interest Calculator

  1. Initial balance
  2. Annual interest rate
  3. Term
  4. Additional deposits
  5. Deposit frequency

Results update as you type, and every field accepts the units shown in its menu.

How it works

Enter the initial balance, interest rate, term and any regular deposits.

Tips

  • Use the nominal annual rate and pick the compounding frequency your bank or broker states.
  • Small differences in return or fees compound into large differences over decades.
  • Run the calculation with a cautious, a central and an optimistic return to see the range of outcomes.
  • Past returns do not guarantee future returns – nothing here is investment advice.

Common mistakes to avoid

  • Comparing an APR with an APY or effective rate.
  • Ignoring inflation, taxes and fees when judging a real return.
  • Entering a percentage as a decimal (5 instead of 0.05 is correct here).

Inputs explained

Field What to enter
Initial balance Amount in your currency
Annual interest rate In %
Term Units: years, months
Additional deposits Amount in your currency
Deposit frequency Choose one: Monthly, Bi-weekly, Weekly, Quarterly …

Example values

How the main result changes when Initial balance changes and everything else stays at the example values above:

Initial balance Final balance
5,000 8,243.61
7,500 12,365.41
10,000 16,487.21
12,500 20,609.02
15,000 24,730.82
20,000 32,974.43

Formula

A = P × e^(rt)With deposits: + C × [(e^(r/f))^(f t) − 1] ÷ (e^(r/f) − 1)Effective annual rate = e^r − 1

Worked example

Inputs — Initial balance: $10,000; Annual interest rate: 5 %; Term: 10 years; Additional deposits: $0; Deposit frequency: Never.
Results — Final balance = $16,487.21; Compound interest = $6,487.21; Effective annual rate = 5.1271 %; Same with monthly compounding = $16,470.09.

Frequently asked questions

What is continuous compounding?

Compounding infinitely often – the limit as the number of periods goes to infinity.

What is the formula?

A = Pe^(rt), where e ≈ 2.71828.

Is it much better than daily compounding?

No – the difference is a tiny fraction of a percent.

What formula does the Continuous Compound Interest Calculator use?

A = P × e^(rt).

Cite this calculator

Speedy Calculator. (2026). Continuous Compound Interest Calculator. Speedy Calculator. https://speedycalculator.com/calculators/finance/continuous-compound-interest/