You can test your ketone levels using urine strips, blood ketone meters, and breath ketone meters. Blood meters, which test for BHB, are considered the gold standard. Breath analysis has been shown to be effective at measuring acetone, while urine analysis measures acetoacetate. Urine strips can provide good feedback at the beginning of the diet, but once you’re keto-adapted and using ketones more efficiently, fewer ketones are expelled in the urine, so they are not a reliable indicator of degree of ketosis.