Cost-Benefit Analysis Calculator
Cost-benefit analysis (CBA) is a structured method for evaluating whether the total benefits of a project or investment justify its total costs. This calculator computes the benefit-cost ratio (BCR), net present value (NPV) of the net benefit, and simple payback period. Enter total project costs, total quantified benefits, annual recurring net benefit, and a discount rate to evaluate the viability of any project over your chosen time horizon.
Cost-benefit analysis formulas
Benefit-Cost Ratio (BCR) = Total Benefits / Total Costs
Net Benefit = Total Benefits - Total Costs
Simple Payback Period = Initial Investment / Annual Net Benefit
NPV = Sum of (Annual Net Benefit / (1 + r)^t) for t = 1 to n
In the NPV formula, r is the discount rate (as a decimal) and t is the year number. A positive NPV means the project creates value above the required rate of return. These formulas are standard in financial analysis and public sector evaluation frameworks.
Interpreting your CBA results
- BCR above 1.0: benefits exceed costs. The higher the BCR, the more value the project creates per dollar spent.
- BCR below 1.0: costs exceed benefits. Reject the project or seek ways to increase benefits or reduce costs.
- A positive NPV means the project exceeds your discount rate (cost of capital) hurdle. It creates value even accounting for the time value of money.
- Shorter payback periods reduce risk: the investment is recovered faster, reducing exposure to future uncertainty.
- Sensitivity analysis is critical: test how BCR and NPV change if benefits are 20% lower or costs are 20% higher than expected.
Cost-benefit analysis: frequently asked questions
What is a cost-benefit analysis?
A cost-benefit analysis (CBA) is a systematic approach to evaluating whether the benefits of a project or decision outweigh its costs. It originated in public policy economics and is now widely used in business investment decisions. The core output is the benefit-cost ratio (BCR): a BCR above 1.0 means benefits exceed costs.
What is the benefit-cost ratio?
The benefit-cost ratio (BCR) = Total Benefits / Total Costs. A BCR of 2.0 means you get $2 in benefits for every $1 spent. A BCR below 1.0 means costs exceed benefits and the project destroys value. BCR is widely used in government project evaluation and infrastructure investment decisions.
How is payback period calculated?
Payback period = Total Initial Cost / Annual Net Benefit. It tells you how many years (or periods) it takes for the cumulative benefits to equal the initial investment. A shorter payback period is generally preferred, though it does not account for the time value of money.
What is the difference between NPV and BCR?
Net present value (NPV) is the absolute dollar value of benefits minus costs, discounted to today's value. BCR is a ratio. NPV tells you the magnitude of value created; BCR tells you the efficiency (return per dollar spent). Use both: a high BCR on a small project may contribute less total value than a moderate BCR on a large project.
Should I include intangible benefits in a cost-benefit analysis?
Yes, if you can assign a credible monetary value to them. Common approaches include willingness-to-pay surveys, hedonic pricing (for factors like time savings), and avoided cost estimates. Intangible benefits that cannot be monetized should be listed qualitatively alongside the quantitative analysis.
Official sources
- Office of Management and Budget (OMB): OMB Circular A-4, Regulatory Analysis (official U.S. government CBA methodology).
- U.S. Department of Transportation: Benefit-Cost Analysis Guidance.
Reviewed by the CalculatorHub team, edited by James Graham, 14 June 2026. See our methodology.