Heat Input Calculator Home Welding Welding Calculator Heat Input Calculator Heat Input Voltage (V) Current(A) Welding Speed (mm/min or inch/min) Thermal Efficiency (Enter 1 for ASME or refer below for EN ISO 1011-1) Calculate Reset Heat Input (KJ/mm or KJ/inch) = Welding Process Thermal Efficiency Tungsten inert gas (TIG) / gas tungsten arc welding (GTAW) 0.6 Plasma arc welding (PAW) 0.6 Metal inert/active gas (MIG/MAG) / gas metal arc welding (GMAW) 0.8 Flux cored arc welding (FCAW) / Metal cored (MCAW) 0.8 Manual metal arc welding(MMA)/shielded metal arc (SMAW) 0.8 Submerged arc welding (SAW) 1