What is compound interest?

Compound interest is interest calculated on both your principal and accumulated interest. It causes investments to grow exponentially over time, often called the eighth wonder of the world.

What is a realistic annual return to expect?

The US S&P 500 has historically returned about 10% annually (7% adjusted for inflation) over long periods. Bond funds typically return 3 to 5%. Individual stocks vary greatly.

How does inflation affect investment returns?

Inflation erodes purchasing power. A 10% nominal return during 3% inflation yields only 7% real return. Always consider inflation-adjusted returns for long-term planning.

What is the Rule of 72?

Divide 72 by the annual interest rate to estimate how many years it takes to double your money. At 8% return, money doubles in approximately 9 years.

← Alle værktøjer / Investment Calculator

📈

Lommeregner for investeringsafkast

Calculate how your investments grow over time with compound interest. See yearly projections, total returns, and compare different contribution strategies.

Initial Investment ($)

Månedligt bidrag ($)

Årlig rente (%)

Investment Period (Years)

1 yr20 år50 yrs

Compound Frequency

Inflation Rate (%) (optional)

Final Portfolio Value

in 20 years

Year-by-Year Growth

How Compound Interest Works

Compound interest is interest earned on both your principal og your previously earned interest. Albert Einstein reportedly called it "the eighth wonder of the world." The key formula is A = P(1 + r/n)^(nt) + PMT × [(1+r/n)^(nt) - 1] / (r/n).

The most important factor is time. Starting 10 years earlier can double your final portfolio. The earlier you start, the more compound interest works in your favor.

Related Financial Tools

Renteberegner
Pensionsberegner
Besparelsesberegner
Pantlån Lommeregner
← Alle værktøjer