 The investigators propose a randomized cross-over study Phase 1 Clinical trial. 30 type 1 diabetes adult outpatients using insulin pumps and continuous glucose monitoring system will be recruited from the Endocrinology Clinic at the Mayo Clinic Arizona. Participants will be randomly assigned to 4 weeks of using their pump bolus wizards to decide insulin boluses and then 4 wks of using iDECIDE to receive recommendations for insulin dosing, or vice versa. The primary outcomes to compare iDECIDEs insulin dosing algorithm against the pump calculators will be: mean postprandial glucose level and number of events with excessive blood glucose highs and lows. 