NPV & IRR Calculator
Discount future cash flows and compute the net present value and internal rate of return.
Inputs
NPV β₯ 0: accept the project.
How it works
NPV = Ξ£ CF_t / (1+r)^t. IRR is the discount rate at which NPV = 0 β computed by bisection.
Frequently asked questions
Are these returns guaranteed?
No β projections assume your inputs hold steady. Real markets fluctuate; treat results as planning estimates.
What's a reasonable long-term return?
Diversified U.S. stock portfolios have averaged 7β10% before inflation over the long run.
Should I include inflation?
Yes if you care about purchasing power. Use a real return = nominal return β inflation rate.
Do taxes affect this?
Inside tax-advantaged accounts (401k, IRA, HSA) growth is tax-deferred or tax-free. Taxable accounts pay annual tax on distributions and on gains when sold.
Does dollar-cost averaging help?
It smooths timing risk and is a behavioral win even if a lump-sum invested earlier has higher expected return.