Compound Interest Calculator
Project how a lump sum (plus optional monthly contributions) grows over time.
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projected value
| Total contributed | — |
| Total interest earned | — |
- What formula does this use?
- The standard compound interest formula A = P(1 + r/n)^(nt) for the lump sum, plus a future-value-of-annuity calculation for any monthly contributions, converted to an equivalent monthly rate so the two combine correctly.
- Does this account for inflation or tax?
- No — this shows nominal growth only. Real (inflation-adjusted) returns and any tax on interest/gains would reduce the actual purchasing power of the result.