CLEP Study Guide
What's on the exam, which units to prioritize, the best free resources — and a 3-minute check to know if you're ready.
Pass Rate
30-40%
Published CLEP data
Prep Time
15-25h
Typical for first attempt
Units
5
Covered on the exam
CLEP Biology covers general college biology. Exam: 115 questions, 90 minutes. Passing earns 6 credits (~$2,400 savings). Content: molecular/cellular (33%), organismal (34%), population/ecology/evolution (33%). Cognitive: 30-40% Recall, 40-50% Understanding, 20-30% Application.
Unit 1: Molecular and Cellular Biology
cell membrane transport · enzyme kinetics · cellular respiration
Unit 2: Genetics and Molecular Biology
Mendelian inheritance · DNA replication · gene expression
Unit 3: Evolution and Diversity
natural selection · speciation · phylogenetics
Unit 4: Organismal Biology
plant structure/function · animal organ systems · homeostasis
Unit 5: Ecology and Population Biology
energy flow and trophic levels · biogeochemical cycles · population growth models
Cognitive: 30-40% Recall, 40-50% Understanding, 20-30% Application.
Translation: rote memorization alone gets you about a third of the way. The rest comes from recognizing patterns and applying concepts — that's where a curated study guide beats crowd-sourced flashcards.
These are the best free resources for CLEP Biology. Use them, then come back here for exam-format practice and a pass-probability check.
Modern States: Biology
Modern States (College Board partner)
Free full video course. Earn the free CLEP voucher after 70% completion.
OpenStax: Biology 2e
OpenStax (free, peer-reviewed)
Cell biology, genetics, evolution, ecology — full CLEP scope.
Khan Academy: Biology
Khan Academy
Cells, genetics, evolution, physiology.
YouTube: CrashCourse
YouTube
40 episodes covering the full CLEP Biology outline.
Before you study anything, know where you stand. You'll get a pass-probability, a weakest-unit callout, and an estimate of hours to ready. No signup.
Don't re-watch content you already know. Drill the 1-2 units flagged as weak. Exam-format flashcards + MCQs give you the question patterns, not just terms.
Simulate the real CLEP under time pressure. Hit 50+ and you're ready to book the test. Miss it, and you'll know exactly which unit to revisit.
Free Am I Ready assessment. No credit card, no signup.
Start the 3-minute check