What C/P actually tests
C/P covers general chemistry, physics, organic chemistry, and biochemistry as they apply to living systems. Passages are frequently experiment-based, and many questions ask you to set up and estimate calculations without a calculator.
The section rewards two distinct skills: content fluency (knowing the relationships) and quantitative rhythm (setting up problems quickly and estimating cleanly under time pressure). Students often have one without the other.
Reading a 128 honestly
A 128 in C/P is in the 85th percentile on the official AAMC section table, in the upper part of the 118 to 132 scale. This is a strong section score, and on a retake the first job is protecting it.
If you are retaking for other sections, keep this one warm with light, regular practice rather than heavy re-study. Strong sections drop when they get ignored for months, not when they get maintained.
How Retakers move this section
C/P improvement on a retake usually starts with separating calculation misses from reasoning misses. A wrong setup means a content fix. A right setup with a wrong final choice usually means a trap or units slip, which is a different kind of practice entirely.
Mental math is trainable and high-yield here. So is drilling official material: the AAMC Chemistry Question Pack for volume and the C/P Section Bank for the reasoning-heavy top end.
Common questions
Is a 128 C/P score good?
A 128 in C/P is in the 85th percentile on the official AAMC section table, meaning 85% of section scores were equal to or lower. Whether it is strong enough depends on your total score, your section balance, and your target programs.
What percentile is a 128 in C/P?
On the AAMC section percentile table in effect May 1, 2026 to April 30, 2027, a 128 in C/P is in the 85th percentile.
How do Retakers improve C/P?
C/P improvement on a retake usually starts with separating calculation misses from reasoning misses. A wrong setup means a content fix. A right setup with a wrong final choice usually means a trap or units slip, which is a different kind of practice entirely.
See the fuller picture
Section scores only mean something in context. For scale, a 128 across all four sections would land near a 512 total. Compare nearby C/P scores: a 127 in C/P and a 129 in C/P, or see how a 128 reads in the other sections: CARS · B/B · P/S.
For a personalized read on your whole score report, start with the free Retaker Calculator, and when you are ready to build the plan, The Retaker Course schedules your C/P work for you.