If you are not in ketosis (or not following a keto diet), the urine ketone levels will be negative (given the absence of diabetes).
When following a keto diet, gradually, the urine ketone levels increase. Any level above negative (i.e., trace, moderate, or large) indicates that your body is metabolizing fat. Ketone levels of 0.5 to 3.0 millimoles per liter (mmol/L) indicate that you are in nutritional ketosis, which is generally the target of a keto diet. Remember that your urine ketone levels can change throughout the day, so it is helpful to check frequently.
Urinalysis strip (dipstick) is a narrow plastic strip which has several square-shaped pads of different colors attached to it. Each small pad represents a component of the test used to interpret urinalysis. When dipped in the urine, pad colors change in response to the chemical characteristics of the urine. The color changes are noted at specific time intervals and compared against the reference color chart/key.