Most students who sit it get a 3 or higher: 70.4% in May 2025. A 5 is harder, at 18.9%. The difficulty is less the facts than applying them to new experiments and data.
Students in May 2025
287,232
Scored 3 or higher
70.4%
Scored 5
18.9%
Mean score
3.24
What makes it hard
Breadth: eight units, from the chemistry of water to ecosystems.
Data: many questions give an experiment, a table or a graph you have never seen and ask what it shows.
Writing: half the score is free response, where each point needs a precise description, explanation or justification.
Maths: rates, percent change, water potential, Hardy-Weinberg and chi-square tests, with a calculator and the reference sheet.
What makes it easier
The course is the same eight units every year, with published weights, so you can plan your time.
Free-response question types and point values stay the same from year to year.
Practice with data and written answers raises scores faster than rereading notes.
Try 2 questions
Question 1
Students cross two pea plants that are heterozygous for height and count 290 tall and 110 short offspring. They test the hypothesis of a 3:1 ratio with a chi-square test. The critical value at p = 0.05 with 1 degree of freedom is 3.84. Which conclusion is correct?
Question 2
Energy stored at four trophic levels of a lake
Trophic level
Energy stored (kJ/m² per year)
Producers
8,000
Primary consumers
640
Secondary consumers
48
Tertiary consumers
4
The table shows the energy stored each year at four trophic levels of a lake. What percent of the energy at the primary consumers is stored at the secondary consumers?
In May 2025, 70.4% of the 287,232 students who took AP Biology scored 3 or higher. Many US colleges grant credit or placement for 3 and above, but each college sets its own policy.
What share of AP Biology students earn a 5?
18.9% in May 2025 (54,186 students).
Is AP Biology harder than AP Chemistry?
They test different skills. AP Biology is broader and leans on reading data and writing explanations; compare your strengths with the units of each course.