Women set a higher bar for confidence: a domain-graded gender difference in local and global metacognitive bias

Confidence influences how people judge their abilities and communicate what they know. Women often report lower confidence than men, even when their performance is comparable, but the basis of this gender gap remains unclear. Here we show that women set higher thresholds for confidence, without evidence that they are less able to recognise when their decisions are correct. Using signal-detection modelling, we examined confidence across memory, perception and general knowledge in 318 adults, with an independent replication of the knowledge tasks in 456 adults. The confidence gap varied markedly by domain, being largest for socioeconomic knowledge and smallest for nutritional knowledge in both samples. More negative self-evaluation was also evident in broader beliefs about ability: women underestimated their overall performance more than men and revised their estimates further downward after testing, widening the gap. Together, these findings suggest that women’s lower confidence reflects more conservative confidence thresholds and more negative self-beliefs, without evidence of poorer performance monitoring.