COCOMO II Cost Calculator
Cost a COCOMO II effort estimate at your own person-month cost.
In short
Cost a COCOMO II effort estimate at your own person-month cost.
Formula: PM = 2.94 × KSLOC^(0.91 + 0.01 × ΣSF) × ΠEM; Cost = PM × Loaded cost per person-month + Non-labour cost
What this calculator does
Effort from the published post-architecture equation with constants A = 2.94 and B = 0.91, then costed at the user's own person-month cost. The nominal scale-factor sum and nominal multiplier product are shown as published defaults and may be changed.
Use it to turn Currency, Size, Sum of the five scale factors, Product of the effort multipliers, and the other shown inputs into a checked result you can compare, copy, or rerun with different assumptions.
The page shows the formula, a numeric worked example, and the assumptions that affect this professional & industry calculation.
Inputs and what they mean
- Currency
- — Amounts are shown in the currency you pick. No exchange rate is applied..
- Size
- — Thousands of source lines of code..
- Sum of the five scale factors
- — Your own ratings for precedentedness, flexibility, risk resolution, team cohesion and process maturity. 18.97 is the published nominal sum..
- Product of the effort multipliers
- — Multiply your rated effort multipliers together; 1 means nominal..
- Loaded cost of one person-month
- — number value.
- Tools, licences and other non-labour cost (optional)
- — Optional component. Leave at 0 to exclude it from the result..
How to use it
- Enter your own figures — the calculator never fills in a rate, price or benchmark for you.
- Press Calculate to see the result.
- Read the formula, variables, assumptions and source below the result before you rely on it.
Formula
PM = 2.94 × KSLOC^(0.91 + 0.01 × ΣSF) × ΠEM; Cost = PM × Loaded cost per person-month + Non-labour cost.
Inputs used: Currency, Size, Sum of the five scale factors, Product of the effort multipliers, Loaded cost of one person-month, Tools, licences and other non-labour cost (optional).
Edge handling: Size is required.; Size must be greater than zero.; Size must be no more than 100000.; Sum of the five scale factors is required.; Sum of the five scale factors cannot be negative..
Worked example
100 KSLOC at your own person-month cost
- Start with Currency: USD, Size: 100, Sum of the five scale factors: 18.97, Product of the effort multipliers: 1, Loaded cost of one person-month: 14000, Tools, licences and other non-labour cost (optional): 0.
- Apply the method: PM = 2.94 × KSLOC^(0.91 + 0.01 × ΣSF) × ΠEM; Cost = PM × Loaded cost per person-month + Non-labour cost.
- Published COCOMO II constants with your ratings; the money figure is yours.
Reading the result
The headline figure is the main answer. Any breakdown underneath shows the parts that make it up, so you can check the working and see what changes when you adjust an input.
Limitations and assumptions
- Inputs outside the supported range are rejected rather than forced into a result.
- The result depends on the values you enter for this cocomo ii cost calculator; it does not supply missing rates, rules, prices, dates, or assumptions for you.
Reference: University of Southern California, Center for Systems and Software Engineering — COCOMO II model definition manual
Last reviewed:
Common questions
Where does this formula come from?
COCOMO II Model Definition Manual — post-architecture effort PM = A × Size^E × ΠEM with A = 2.94 and E = B + 0.01 × ΣSF (B = 0.91), and schedule TDEV = C × PM^(D + 0.2 × (E − B)) × SCED%/100 with C = 3.67 and D = 0.28. See the source link on this page.
What kind of calculation is this?
The published post-architecture effort equation, costed at the loaded person-month cost the organisation enters. Check the formula, example, and limitations on this page before using the result for a real professional & industry decision.
What are its limits?
COCOMO II is a calibrated estimation model, not an exact prediction; its published accuracy is a range, not a point. Estimates are only as good as the size, scale factors and effort multipliers entered.
How do I use the COCOMO II Cost Calculator?
Enter the required values for Currency, Size, Sum of the five scale factors, Product of the effort multipliers, Loaded cost of one person-month, and the other fields shown. The calculator applies the formula on this page and shows the main result with any supporting breakdown so you can check the arithmetic.
What formula does the COCOMO II Cost Calculator use?
PM = 2.94 × KSLOC^(0.91 + 0.01 × ΣSF) × ΠEM; Cost = PM × Loaded cost per person-month + Non-labour cost The visible formula section above lists the calculation path and the edge cases the page handles, so the result can be checked without relying on the form alone. Check the formula, example, and limitations on this page before using the result for a real professional & industry decision.
Can the COCOMO II Cost Calculator be used for exact decisions?
Use it as a calculation aid, not as a substitute for checking the underlying rule, contract, policy, or professional advice that applies to your situation. When a result depends on local rules, personal details, prices, or dates, enter those values yourself and confirm them before acting.
Formula, source and verification
The published post-architecture effort equation, costed at the loaded person-month cost the organisation enters.
The question it answers: What will this development cost, using the published estimation model?
The formula
PM = 2.94 × KSLOC^(0.91 + 0.01 × ΣSF) × ΠEM; Cost = PM × Loaded cost per person-month + Non-labour cost
- Size — Size
- (KSLOC). Thousands of source lines of code.
- ΣSF — Sum of the five scale factors
- (points). The organisation's own ratings; 18.97 is the published nominal sum.
- ΠEM — Product of the effort multipliers
- (factor). The organisation's own rated multipliers; 1 is nominal.
- c — Loaded cost of one person-month
- (currency). Employer cost of one person-month, entered by the organisation.
- N — Non-labour cost
- (currency). Optional tools, licences and other non-labour cost.
Units: KSLOC; person-months; currency.
What kind of calculation this is
Estimation model. This is a published estimation model. It produces an estimate, not a measured fact, and its accuracy depends on how well your situation matches the model.
Method
Effort from the published post-architecture equation with constants A = 2.94 and B = 0.91, then costed at the user's own person-month cost. The nominal scale-factor sum and nominal multiplier product are shown as published defaults and may be changed.
Assumptions built into the result
- Industry: Size, scale factors and effort multipliers are rated by the user under the published rating scales.
Figures this calculator will never guess for you
- No industry delivery rate, productivity figure, defect rate or cost per line is inserted.
- No optional component is filled in on the user's behalf.
- No person-month cost is supplied by the calculator.
Limitations
- COCOMO II is a calibrated estimation model, not an exact prediction; its published accuracy is a range, not a point.
- Estimates are only as good as the size, scale factors and effort multipliers entered.
Source and version
- Standard or reference
- COCOMO II post-architecture model — University of Southern California, Center for Systems and Software Engineering (COCOMO II Model Definition Manual — post-architecture effort PM = A × Size^E × ΠEM with A = 2.94 and E = B + 0.01 × ΣSF (B = 0.91), and schedule TDEV = C × PM^(D + 0.2 × (E − B)) × SCED%/100 with C = 3.67 and D = 0.28.)
- Published source
- University of Southern California, Center for Systems and Software Engineering — COCOMO II.2000
- Formula version
- Version 1
- Verification
- Reviewed against the cited source on
- How much weight the source carries
- Academic
- Applies to
- Currency
- Amounts stay in the currency you choose; no exchange rate is applied.
Cite this page
Free Calculator. (2026, September 16). COCOMO II Cost Calculator. https://freecalculator.tech/tools/cocomo-ii-cost-calculator
"COCOMO II Cost Calculator." Free Calculator, 16 Sept. 2026, https://freecalculator.tech/tools/cocomo-ii-cost-calculator.
COCOMO II Cost Calculator — Free Calculator, https://freecalculator.tech/tools/cocomo-ii-cost-calculator
Related tools
Work out the hourly rate to charge a client so that target margin is met after overhead and non-billable time.
Find the true hourly cost of an employee once benefits, payroll cost and overhead are included.
Size a software application from its data and transaction functions before estimating effort or cost.
Estimate development effort, schedule and average team size for a software project of a known size.
Express cloud spend as a cost per customer, per transaction or per other business unit.
Set the rate used to apply manufacturing overhead to jobs for the coming period.