Compound Interest Calculator

Calculate the power of compound interest for your savings and investments.

$
%
Total Value2,427,262$
Total Principal1,000,000
Total Interest1,427,262

The Magic of Compound Interest

Compound interest is the interest on a loan or deposit calculated based on both the initial principal and the accumulated interest from previous periods. Einstein called it the "Eighth Wonder of the World" for its power to grow assets exponentially over time.

Why is it important?

Unlike simple interest, which only applies to the principal, compound interest reinvests your earnings. This creates a "snowball effect" where your wealth grows slowly at first but accelerates rapidly as the interest itself starts earning more interest.

How to Use Each Mode

Our calculator offers three specialized modes to fit your investment strategy.

Mode 1
Standard (Lump Sum)

Ideal for one-time investments. Calculate how a single deposit grows over time with various compounding frequencies.

Example: See the result of $10,000 invested at 5% for 10 years.
Mode 2
Savings (Accumulation)

Designed for regular saving habits. Factor in an initial deposit plus monthly contributions to see your long-term wealth building progress.

Example: $5,000 initial + $1,000/month for 20 years to reach $1M.
Mode 3
Target Goal

Goal-oriented planning. Determine how much time or what interest rate is required to reach your financial milestones.

Example: What rate is needed to turn $100k into $300k in 10 years?

The Power of Compounding Frequency

The frequency with which interest is compounded affects the final amount. The more often interest is added to the principal, the faster the balance grows.

Main Frequencies
  • Yearly: Interest is added once a year. Common for fixed deposits.
  • Quarterly: Every 3 months. Useful for dividend-paying stocks.
  • Monthly: Every month. The most common standard for regular savings.
  • Daily: Every day. The most powerful effect, often seen in crypto staking.
Compounding$10,000 Investment (10% APR, after 10 years)Difference
Simple20,000 / 2,000만원-
Yearly (1/year)25,930 / 2,593만원Ref.
Monthly (12/year)27,070 / 2,707만원+114
Daily (365/year)27,170 / 2,717만원+124

Mathematical Formulas

Standard financial formulas used in this calculator.

Standard Compound

A = P(1 + r/n)^(nt)

A: Final Value, P: Principal, r: Annual Rate, n: Freq, t: Years

Savings Accumulation

A = P(1+r/n)^(nt) + PMT * [((1+r/n)^(nt) - 1) / (r/n)]

PMT: Regular Payment. The second term represents the future value of the annuity.

Target Time (Logarithm)

t = [log(target) - log(P)] / [n * log(1 + r/n)]

Calculates the required time (t) using log functions based on target (A) and initial (P).

3 Tips for Wealth Growth

Time Over Speed

Consistency and time are more important than chasing high-risk short-term gains. The longer you stay in the market, the stronger the magic.

Consider Inflation

A dollar tomorrow is worth less than a dollar today. Aim for targets that account for a 2-3% annual inflation rate.

The Rule of 72

Estimated time to double your money = 72 divided by the growth rate. (e.g., 6% growth doubles in 12 years).

Simulations are for educational purposes only. Actual returns may vary due to taxes, fees, and market volatility.