Cost-Benefit Analysis Calculator

Evaluate public projects with NPV, benefit-cost ratio, payback period, and internal rate of return.

Inputs

Project Cost ($)

Annual Benefit ($)

Discount Rate (%)

Project Life (years)

Tab to move between fields

Results

Net Present Value (NPV)

$2,361,774.00

≈ 6 average U.S. homes

IRR (%)

16.7%

Benefit-Cost Ratio2.18

Payback Period (years)5.7

How to Use This Calculator

Enter the Total Project Cost and the estimated Annual Benefit in dollars.
Enter the Social Discount Rate (OMB recommends 3–7% for public projects) and Project Life in years.
Review the Net Present Value (NPV) — a positive NPV means benefits exceed costs in present-value terms.
Check the Benefit-Cost Ratio: values above 1.0 indicate the project is economically justified.
Use Payback Period and Internal Rate of Return (IRR) to compare alternative projects.

How the result changes with Annual Benefit ($)

Annual Benefit ($)	Net Present Value (NPV)	IRR (%)
$1,000,000,000.00	$12,460,210,343.00	100%
$3,500,000,000.00	$43,615,736,199.00	100%
$6,500,000,000.00	$81,002,367,227.00	100%
$9,000,000,000.00	$112,157,893,083.00	100%

What each input means

Project Cost ($): Total upfront cost of the public project
Annual Benefit ($): Estimated annual monetary benefit (cost savings, revenue, economic value)
Discount Rate (%): Social discount rate for public projects (OMB recommends 3-7%)
Project Life (years): Expected useful life of the project in years

How this is calculated

Worked example, using the default values

Identify Input Parameters
4 parameters
Project Cost ($) = 2000000, Annual Benefit ($) = 350000, Discount Rate (%) = 5, Project Life (years) = 20 = 4 input(s) provided
Calculate Net Present Value
Net Present Value
2361774 = $2,361,774
Calculate IRR
IRR
16.7 = 16.7
Calculate Benefit-Cost Ratio
Benefit-Cost Ratio
2.18 = 2.18
Calculate Payback Period
Payback Period
5.7 = 5.7

Engine last updated August 4, 2026. Checked against 2 independently-derived tests — how we verify calculators.

The questions that sit next to this one — chosen by subject, including calculators filed under a different category.

Government Finance

Budget Variance Calculator

Analyze department budget variance, project year-end spending, and identify over/under budget status.

Government Finance

Municipal Bond Payment Calculator

Calculate annual debt service payments, total interest, and total cost for municipal bonds.

Investing & Retirement

IRR Calculator

Calculate Internal Rate of Return (IRR) for an investment with multiple cash flows. Essential for comparing investment opportunities and project analysis.

Project Management