Welder certification, also known as welder qualification is a process which examines and documents a welder's capability to create welds of acceptable quality following a well defined welding procedure. The welds are spot tested using non destructive methods to ensure their quality. A Welding Procedure Specification (WPS) is the formal written document describing welding procedures, which provides direction to the welder or welding operators for making sound and quality production welds as per the code requirements.

Qualification welds are typically examined using ultrasonic inspection to detect internal flaws, while hardness testing is performed to verify that weld and heat-affected zone properties meet the required specifications.