The Fitbit 
                                Aria Air is part of the
                                Bathroom Scales test program at
                                Consumer Reports.  In our lab tests, Smart Bathroom Scales
                                models like the Aria Air are rated on multiple criteria, such as those
                                listed below.
                            
                                                        
                                Accuracy:
                                A high score means the scale accurately measures weight. A top-scoring model has an accuracy of 99.5% or greater.
                            
                                                        
                                Consistency:
                                A high score means the scale gives repeatable results. A top-scoring model reliably reflects real weight changes.
                            
                                                        
                                Unbalanced weighing:
                                A high score means the scale gives repeatable results even if your weight isn’t evenly distributed. A top-scoring model works reliably without perfect foot placement.