Practice testing is a highly robust learning strategy that promotes long-term retention, especially in comparison to more passive strategies such as restudying-a finding referred to as the testing effect. However, learners do not always appreciate the memorial benefits of practice testing over restudying, which could limit their use of practice testing during self-regulated learning. The current investigation explored the extent to which learners' metacognitive judgments about the testing effect can be improved via test experience, direct instruction, or a combination of both techniques. Prolific participants underwent two learning cycles. In the first cycle, participants were randomly assigned to either (a) experience a testing effect in their own memory performance (i.e., study unrelated word pairs, practice half the pairs through restudying and half through testing with correct-answer feedback, complete a critical test on the pairs, and receive feedback regarding their performance after using each strategy); (b) imagine they had to learn word pairs and read a passage on the purported benefits of practice testing; or (c) undergo both procedures. In the second cycle, all participants learned a novel set of word pairs. Across both learning cycles, participants estimated memory performance for material learned through testing versus restudying. Both test experience and direct instruction-independently and in combination-led to more accurate memory estimates across learning cycles, but no technique was more effective than the other. In summary, people can learn about the memorial benefits of practice testing when they experience a testing effect on their own memory performance and/or when they receive instruction about its benefits.