The two basic principles of the problem in assessment are determining whether a test has measured what is being measured and whether a test has been appropriately used to make a decision about the test taker. It is possible that the test developers argue that math tests for example can predict a person’s ability in physics. Validity or validity comes from the word validity, which means the extent of accuracy and accuracy of a measuring instrument in performing its measuring function. In other words, validity is a concept related to the extent to which the test has measured what should be measured. In this study discusses the meaning of validity, types of validity, testing the validity of tests, testing the validity of tests rationally, construct validity, content validity, testing the validity of tests empirically, forecast validity, comparative validity, question validity, and validity testing calculations. items of measurement results. With the method of quantitative data analysis, the results of the research from the distribution of questionnaires to 20 (twenty) respondents, 10 (ten) of them were tested for validity and it was found that 7 (seven) items were valid and 3 (three) invalid.