Lumpsum Calculator

A lumpsum investment puts a whole amount to work at once, rather than in instalments. It's how people typically invest a bonus, a maturing fixed deposit, an inheritance or the money from selling property.

This calculator projects the value of that single investment over time at a steady expected return. It shows the final value, the total gain, how many times the money multiplies, and how long it takes to double, along with the value at the end of each year. Use it to compare expected returns from different investments, or to see what leaving money invested a few more years achieves.

A lumpsum grows by the formula A = P × (1 + r)^t, with P the amount invested, r the yearly return and t the number of years. Each year's return is earned on the original amount plus every earlier year's return.

The doubling time shown uses the exact formula ln 2 ÷ ln(1 + r). The rule of 72 gives a quick estimate: divide 72 by the return, so 12% doubles money in about 6 years.