John Test is the cousin of Johnny Test. He is only 7 years old and tries to be like Johnny. He sometimes plays with Susan and Mary's experiments and has been known to dislike Dukey for being around Johnny.

Ad blocker interference detected!

Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.