Usability evaluation of a complete or near-complete design under realistic conditions that can be used to determine if the design meets specific measurable performance and/or satisfaction goals, or to establish a usability benchmark or to make comparisons.

This approach is in contrast to a formative evaluation which is used to find and eliminate problems during the design and development process, rather than judge a completed product against specific goals.

Both summative and formative refer to the purpose of the evaluation.