Tool

Carbon equivalent (Ceq) calculator

Enter the element percentages from your plate's mill test certificate to calculate carbon equivalent using the IIW formula and get general weldability guidance.

Carbon (C) is required. Other elements default to 0 if left blank.

Exact preheat temperature depends on section thickness, hydrogen level and joint restraint, not on Ceq alone. Confirm against the actual mill test certificate's Ceq, the joint's welding procedure specification (WPS), and classification-society requirements — this tool is for general reference, not a substitute for a proper WPS.

This calculator gives a general reference value based on the chemistry you enter and is not a formal quotation or a welding procedure. For pricing and lead times against your exact specification, request a formal quotation