I agree with Tara that weighing first thing in the morning is the best time to get an accurate weight result. However, as long as you weigh at the same time every day and under the same conditions (similar clothing, etc.) you should still get an accurate result of pounds lost. With that said - I weigh first thing in the morning butt-naked, cause every ounce counts and I don't want a t-shirt or anything weighing me down! LOL.