Rate of Return Calculator

• •Use the Rate of Return Calculator when solving homework or exam problems that require quick numerical verification of your hand calculations — instant feedback helps identify arithmetic errors before they propagate.
• •Use it during the early design phase to rapidly iterate on parameters and narrow down feasible configurations before committing time to detailed finite element simulations or full design packages.
• •Use it when reviewing a colleague's calculation or checking a vendor's data sheet for plausibility — a quick sanity check can prevent costly downstream errors.
• •Use it to generate reference data for a technical report or presentation without manual computation, ensuring consistent, reproducible numbers throughout the document.
• •Use it in the field when a quick estimate is needed and a full engineering software package is not available.

The Rate of Return Calculator is a precision engineering calculation tool designed for students, engineers, and technical professionals. Incremental IRR analysis comparing two alternatives. Computes IRR_A, IRR_B, incremental IRR, NPV at MARR, and preferred alternative. All calculations are performed using established engineering formulas from the relevant scientific literature and standards. Inputs support both metric (SI) and imperial unit systems, with unit conversion handled automatically — simply select your preferred unit from the dropdown next to each field. Results are computed instantly in the browser without sending data to a server, ensuring both speed and privacy. This calculator is intended as a supplementary tool for learning and design exploration; always verify results against authoritative references for safety-critical applications.

Rate of return is the profit or loss on an investment as a percentage of the amount invested. Simple (arithmetic) return: (ending value + distributions) / starting value − 1. For a $10,000 investment worth $11,500 plus $500 dividends: return = (11,500 + 500)/10,000 − 1 = 20%. Time-weighted return removes the effect of contributions and withdrawals to measure pure investment performance, appropriate for comparing fund managers. Money-weighted return (IRR of cash flows) reflects the actual experience of the investor including timing of contributions. For annualized returns on multi-year investments, use the geometric mean: (ending value / starting value)^(1/n) − 1, where n is years. This accounts for compounding. For comparing investments of different durations, always annualize. Incremental IRR analysis compares two investment alternatives: compute the IRR of the DIFFERENCE in cash flows (A − B). If incremental IRR exceeds the required rate, choose A over B; otherwise B. This handles the common mistake of choosing high-IRR small projects over lower-IRR large projects when the large project creates more total value.

• •Investment portfolio evaluation: compute annualized return on a portfolio to compare against benchmarks and objectives.
• •Private business valuation: compute the IRR of a business's historical cash flows as an input to valuation.
• •Capital project comparison: use incremental IRR to choose between two mutually exclusive investments with different sizes.
• •Lease vs buy analysis: compute IRR of the difference in cash flows between leasing and buying to decide which is more economical.
• •Real estate investment analysis: compute cash-on-cash return, total return, and IRR for rental property investments.