90 to 100F is good. 98 to 102F is perfect. Temperature, of course, is vital. We can buy the best synthetic urine with perfect urea and creatinine levels but every fake pee also has to be heated to the body temperature. Urine for drug tests must not be too hot or too cold. Real urine’s temperature is never above 105F (unless you have a really high fever). It also shouldn’t be below 90F. It should be just right – as if it came out of your body minutes ago.