Fluid vs. Crystallized Intelligence

Fluid intelligence is the ability to reason through new problems you haven't seen before, without relying on prior learned knowledge — the kind of thinking used in pattern recognition and logic puzzles like the ones in our IQ Test.

Crystallized intelligence is built from accumulated knowledge, facts, and skills gathered over a lifetime — vocabulary, general knowledge, and learned procedures fall into this category.

How they tend to change over a lifetime

Fluid reasoning speed is often described as peaking relatively early in adulthood, while crystallized knowledge tends to keep building well into later life. Both contribute to overall cognitive performance in different ways, which is part of why a single test score is a limited snapshot rather than a full picture.