IRR Calculator

The internal rate of return is the discount rate that makes the net present value of a series of cash flows exactly zero. Type the flows in order starting with period 0, using negative figures for money paid out, and add a discount rate if you also want the net present value. There is no closed formula once the flows are uneven, so the rate is found by bisection, narrowing the bracket until the two ends agree to within 1e-10, which is far tighter than the four decimal places shown. A series whose flows never change sign has no internal rate of return, and that is refused with a message rather than guessed at. When the flows change sign more than once, several rates can solve it, and the tool says so and reports the lowest one it finds.