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KSLOC Calculator

Size software in thousands of source lines, counted or converted.

Two published ways to reach a size. They are not combined.

Line count

Used by the source-line method.

Function point conversion

Used by the conversion method.

Taken from your own codebase in your own language. No conversion table is supplied.

Press Calculate, or Enter in any field.

128,400 source lines

A straight line count; the conversion method stays a separate choice.

What this calculator does

COCOMO II takes size in KSLOC and documents conversion from functional size using a language-dependent ratio. That ratio must be the organisation's own measured value; the calculator supplies none.

Inputs and what they mean

Sizing method
Two published ways to reach a size. They are not combined..
Source lines of code
Used by the source-line method..
Function points
Used by the conversion method..
Your own lines of code per function point
Taken from your own codebase in your own language. No conversion table is supplied..

How to use it

  1. Enter your own figures — the calculator never fills in a rate, price or benchmark for you.
  2. Press Calculate to see the result.
  3. Read the formula, variables, assumptions and source below the result before you rely on it.

Formula

Line count method: KSLOC = SLOC ÷ 1000. Conversion method: KSLOC = (Function points × Your lines per function point) ÷ 1000

Worked example

128,400 source lines

A straight line count; the conversion method stays a separate choice.

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

Results depend entirely on the figures you enter and are rounded for display. They are for general information and education, not professional advice.

Reference: University of Southern California, Center for Systems and Software Engineering — COCOMO II model definition manual

Last reviewed:

Common questions

Formula, source and verification

Size in thousands of source lines, by either of two published routes. The two routes are separate choices and are never combined.

The question it answers: What size do I feed into the estimation model?

The formula

Line count method: KSLOC = SLOC ÷ 1000. Conversion method: KSLOC = (Function points × Your lines per function point) ÷ 1000

SLOCSource lines of code
(lines). Counted source lines, used by the line count method.
FPFunction points
(FP). Functional size, used by the conversion method.
gLines of code per function point
(lines/FP). The organisation's own ratio for its own language; no conversion table is supplied.

Units: Lines; thousands of lines; function points.

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

COCOMO II takes size in KSLOC and documents conversion from functional size using a language-dependent ratio. That ratio must be the organisation's own measured value; the calculator supplies none.

Assumptions built into the result

  • Operational: Lines are counted under one consistent counting rule.

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 language gearing factor is provided.
  • The two sizing methods are never averaged or combined.

Limitations

  • Converted sizes inherit all the uncertainty of the conversion ratio.
  • A size, not an effort or a cost.

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.)
Formula version
Version 1
Verification
Reviewed against the cited source on
How much weight the source carries
Academic
Applies to
Currency
The result is a ratio or index, so it does not depend on currency.

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