How much do AI answers change between runs?

A lot, and nobody agrees on how much. Ask an AI engine the same question twice and the brands it names can differ.

SparkToro and Gumshoe found less than a 1-in-100 chance of getting the identical brand list twice across 100 runs. MaxAEO found 17% of prompts changed their brand set from one day to the next. Researchers suggest repeating each prompt at least seven or eight times; some vendors run a hundred.

A number from a single run is a coin toss with a decimal point. Every number on this site says how many runs it came from.

Who is speaking: SparkToro, which sells audience research. MaxAEO, which sells AI visibility tracking. Academic researchers. Label: Verified, read in the studies. The studies measure different things, so the figures are not comparable with each other. Source: SparkToro blog, 28 January 2026. MaxAEO blog, 11 June 2026. Schulte et al., 2026.