Transformer sizing calculation based on actual connected or operating load, ANSI & IEC standard types, classes, & ratings. Considers several factors like ambient temperature, altitude, Load Growth factor, Future Spare capacity. Derating factors to be used to determine if a transformer can handle its required operating load. Inadequately sized transformers may shorten the equipment operating life or cause overloading failures. This app will - Convert your load to KVA - Calculate the your required KVA with considering your future growth loads and spare if any - Calculate the min adequate size of transformer suitable for your application , and apply all required de-rated factors for ambient temperature, altitude - Select for you the standard transformer size based of the ANSI & IEC rating with all required detail. - Generate detail calculation report in PDF format for your reference with all details of calculation parameters and equitation, with property of editing and sharing. With more Features such as interaction with users to give some guidelines when you enter the essential data, the primary voltage, secondary voltage, your loads in KW or Amperes, site parameters and your required parameters for load growth and future spare, the app will interact with you so if the voltage inputs is not standard value will give you orange color. Your inputs will be evaluated during interning process, and will give you green (good), orange (not standard value) or red (exceed the standard limits). For Example, three power transformer with 480 V secondary voltage, the maximum available size in the market is 2500/3125 KVA and the primary voltage maximum will be 34.5 KV, this means the app will give you red color if you exceed those limits. The app is deigned to calculate stable transformer size from small sizes such as 0.01 KVA to large sizes 512 MVA transformers. The app cover both single phase and three phase transformers application.