📉 Interest Rate Calculator
Have a savings goal and a deadline? This calculator works the compound-interest formula backwards: given where you are and where you want to be, it solves for the annual rate of return you need.
If the required rate looks unrealistically high, the honest fixes are more time, a bigger starting sum, or regular contributions — not a riskier investment.
How to use this calculator
Enter how much you have now, the goal amount and the years available, and find the annual rate of return you would need to get there.
- Enter the Present amount you are starting with.
- Type the Future goal you want to reach.
- Set the Years to grow available to you.
- Press Calculate to reveal the required annual rate.
Frequently asked questions
What does this calculator solve for?
Instead of projecting growth from a rate, it works backwards: given your present amount, your future goal and the time available, it finds the annual rate of return you would need to bridge the gap.
What is the formula?
It rearranges the compound growth formula: the required rate equals the goal divided by the present amount, raised to the power of one over the years, minus one. The goal must be at least as large as the present amount.
Give me an example.
To turn $10,000 into $20,000 in 10 years you would need an annual return of about 7.18%, because 1.0718 raised to the 10th power is roughly 2.
What if the required rate looks too high?
That is the calculator doing its job. The honest fixes are allowing more time, starting with a bigger sum, or adding regular contributions. Chasing the rate with riskier investments is usually the wrong answer.