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
varies
Published exam 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.
These are the best free resources for CLEP Biology. Use them, then come back here for exam-format practice and a readiness 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.
Amoeba Sisters YouTube
YouTube (student-endorsed)
Real test-takers credit Amoeba Sisters for genes/enzymes/cell-process clarity. Watch when a Khan video doesn't click.
Peterson's CLEP Biology practice tests
Peterson's (paid, optional)
Multiple paid test-takers reference Peterson's as their final practice. Use only if free options don't get you over the line.
Before you study anything, know where you stand. You'll get a readiness signal, 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 exam under time pressure. Miss it, and you'll know exactly which unit to revisit.
Full CLEP Biology prep
Complete breakdown, units, resources, pricing.
3-day pass plan
Day-by-day plan if you're testing this week.
How hard is CLEP Biology?
Difficulty factors, pass rates, what trips people up.
Exam-aligned flashcards
Free preview — 12 cards generated to the blueprint.
Printable cheat sheet
High-yield formulas, facts, and graph-reading rules.
Free readiness check. No credit card, no signup.
Start the 3-minute check