This entry gives a brief introduction to designing effective online quizzes for language learning. It discusses how direct and indirect effects of testing are relevant in the case of online quizzes as assessment and presents the theories and hypotheses underpinning the effects of online quizzes. In addition, it reviews empirical evidence for effective application of online quizzes in foreign language courses. Pedagogical considerations for designing and administering quizzes are covered in detail. This includes evaluating factors such as quiz contents, format, timing of using online quizzes, and types of online quizzes. Finally, the importance of feedback is also addressed by providing the effective timing and types of feedback.