Abstract Laboratory drilling tests have been used successfully to determine the tendency of a PDC drag bit to whirl. Drill bit whirl has been demonstrated in all four drilling simulators where whirl tests were performed. This paper describes the design and testing of anti-whirl PDC drag bits. The verification process of the anti-whirl concept, which includes both laboratory and field tests, will be emphasized. Results from the laboratory drilling experiments that measure a bit’s propensity to vibrate are presented. Additionally, results from more than 60 field runs are summarized and discussed, with three successful field runs discussed in detail.