Enter values and press Calculate to receive your Cognitive Load Score.

The Formula & How to Read Your Score

CFI = (0.5 × Duration) + (2.0 × Complexity) − (1.5 × Familiarity)

The estimator returns a Cognitive Friction Index (CFI). Longer duration and higher complexity raise it; greater prior familiarity lowers it. The score is classified against three fixed bands, exactly as implemented in the tool's source code:

What this is — and isn't. This is a transparent educational heuristic, not a validated psychometric instrument. The coefficients (0.5, 2.0, 1.5) are our own weighting choices, not measured constants. The calculation runs entirely in your browser and stores nothing. For why complexity is weighted above duration, see How It Works.

The research this is grounded in

Working memory — the mental workspace where you actively hold and manipulate information — is sharply limited. Miller's classic 1956 paper estimated its span at roughly "seven, plus or minus two" chunks, and later work by Baddeley and Hitch modelled it as a multi-component system with finite capacity. Sweller's Cognitive Load Theory builds on this: when the number of interacting elements in a task exceeds that capacity, performance and learning degrade. Our three inputs are practical proxies for those demands — complexity approximates element interactivity, familiarity approximates the schemas that let experts chunk information, and duration approximates vigilance attrition over time.

What the research does not say is that a single linear formula can measure an individual's load precisely. It cannot. Use the score to compare tasks and spot saturation risk, not as an absolute reading of any one person's mind.

References

For an applied breakdown of reducing this score in messy environments, read Why We Burn Out: Intrinsic Complexity vs. Extraneous Load.