Combinatorial t-way testing with small t is known as an efficient black-box testing technique to detect parameter inter- action failures. So far, several empirical studies have reported the effectiveness of t-way testing on fault detection abilities. However, few studies have investigated the effectiveness of t-way testing on code coverage, which is one of the most important coverage criteria widely used for software testing. This paper presents a quantitative analysis to evaluate the code-coverage effectiveness of t-way testing. Using three open source utility programs, we compare t-way testing with exhaustive (all combination) testing w.r.t. their code coverage and test suite sizes.