# Compound Interest Calculator

## Online investment compound interest calculator

\$
%
at theperiod
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### Compound Interest

• Compound interest is the interest either loan or deposit, calculated on the initial deposit (principal) and the accumulated interest from the previous period.

Total interest = FV - P
Where:
FV = Future value
P = Initial principal balance

Formula:

FV = P x (
1 +
 r n
)(n x t)

FV = Future value (final amount)
P = The initial investment (initial principal balance)
r = Interest rate
n = Number of times compounded per year
t = Term (number of time periods)

• Formulas if there are contributions:

If the additional deposit is made at the end of the period, it can be the end of the month, quarter, year, etc...

FV = [P x (
1 +
 r n
)(n x t)] + [PMT x [((
1 +
 r n
)(n x t) - 1)
÷
 r n
]]

FV = [P x (1 + r ÷ n )(n x t)] + [ PMT x [((1 + r ÷ n)(n x t) - 1) ÷ (r ÷ n)] ]

FV = [P x (
1 +
 r n
)(n x t)] + [[PMT x [((
1 +
 r n
)(n x t) - 1)
÷
 r n
]]x(
1 +
 r n
)]

FV = [P x (1 + r ÷ n )(n x t)] + [[ PMT x [((1 + r ÷ n)(n x t) - 1) ÷ (r ÷ n)] ] x ( 1 + r ÷ n )]

Where PMT is the additional payment

If the periodic payment doesn't match the frequency of compounding.

Formula will be:

FV = [P x (1 + r ÷ n )(n x t)] + [ PMT x ([(1 + r ÷ n)(n x NP)](NP x t) -1) ÷ [(1 + r ÷ n)(n x NP) -1] ]

Where NP is the number of payment per year