To assess the meaningfulness of an intervention effect on students' achievement, researchers may apply empirical benchmarks as standards for comparisons, involving normative expectations for students' academic growth as well as performance gaps between weak and average schools or policy-relevant groups (e.g., male and female students, students from socioeconomically advantaged or disadvantaged families, students with or without a migration background). Previous research made these empirical benchmarks available for students in the United States. We expand this line of research by providing novel meta-analytic evidence on these empirical benchmarks for students attending elementary and secondary schools in Germany for a broad variety of achievement outcomes. Drawing on the results obtained for large probability samples, we observed variations in each kind of benchmark across countries as well as across and within domains and student subpopulations within Germany. Thus, the assessment of the very same intervention effect may depend on the target population and outcome of the intervention. We offer guidelines and illustrations for applying empirical benchmarks to assess the magnitude of intervention effects.