COCOMO Model Calculator
Estimate software development effort, schedule, and staffing needs with the COCOMO model by supplying the project size and anticipated complexity.
Project Inputs
Enter the size in thousands of lines of code (KLOC) and select the project archetype.
The coefficients (a, b, c, d) update the effort, time, and staffing curves. Organic projects are small teams, embedded projects are highly constrained, and semi-detached sit between.
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How to Use This Calculator
Supply the estimated project size in KLOC (thousands of lines of code) and select the archetype that best matches your context. Click Calculate to see effort in person-months, the anticipated duration in months, and the required headcount.
The reset button restores the default assumptions so you can quickly compare scenarios without reloading the page.
Methodology
The calculator implements Barry W. Boehm’s original COCOMO model parameters. It applies the canonical effort and schedule formulas for organic, semi-detached, and embedded projects. Effort grows as a power of size, while duration is a power of effort, so the outputs change smoothly as the inputs vary.
Results are estimates derived from historical industry data; adjust the input size and type if your project has unusual constraints or an atypical team makeup.
Glossary
- KLOC: Thousands of lines of delivered source code.
- Effort (E): Measured in person-months, the total work required.
- Time (T): Duration in months to deliver the project.
- People (P): Team size approximated as E / T.
Step-by-Step Example
A 50 KLOC organic project yields the standard curves: effort grows gently, scheduling assumes a small, coordinated team, and the people estimate rounds up to the nearest full headcount.
Frequently Asked Questions
What is the COCOMO model?
The Constructive Cost Model is a procedural approach released by Barry W. Boehm to forecast software development cost, duration, and staffing.
How do I pick a project type?
Use Organic for small, stable teams and requirements; Semi-Detached for mixed environments; Embedded for tightly constrained, safety-critical systems.
How accurate are these estimates?
The outputs track the published formulas, but real projects may vary due to organization, tooling, and domain-specific work. Treat these numbers as starting points.
Can COCOMO still be used for modern projects?
Yes. Adjust the KLOC input to reflect modern abstractions and calibrate the project type selection against your team’s delivery history.
Where can I learn more?
Review the original COCOMO paper or the maintained summary on Wikipedia for coefficient tables and refinement steps.