The scale is named after its creator, American chemist Wilbur Scoville, who developed a test for rating the pungency of chili peppers. His method, which he devised in 1912, is known as the Scoville Organoleptic Test.

In Scoville's method, a solution of the pepper extract is diluted in sugar syrup until the "heat" is no longer detectable to a panel of (usually five) tasters; the degree of dilution gives its measure on the Scoville scale. Thus a sweet pepper or a bell pepper, containing no capsaicin at all, has a Scoville rating of zero, meaning no heat detectable, even undiluted. Conversely, the hottest chillies, such as habaneros, have a rating of 200,000 or more, indicating that their extract has to be diluted 200,000-fold before the capsaicin present is undetectable.