hi my children has one and it does tell you when you have lost weight as my daughter did not go on it for a few weeks and it had told her how much she had lost since she last went on it so it must tell you .my daughter thougt it was great as she has been losing weight at slimming world and lost over astone and a half so we knew she had lost the weight but she is very big for her age so shewas pleased to lose it.