Maintainability Index

Maintainability Index combines static measurements—commonly lines of code, Cyclomatic Complexity, and Halstead metrics—into a single score intended to indicate relative maintainability. Exact formulas and score ranges vary by tool.

Interpretation

The index is most useful for tracking trends within the same repository and toolchain. It should not be used as an absolute quality grade or to compare unrelated systems without understanding the formula and language-specific behavior.

A declining score can prompt investigation, but changes should improve clarity and delivery outcomes rather than merely optimize the number.