ETS offers three GRE Subject Tests: Mathematics (about 66 questions, 2 hours 50 minutes), Physics (about 70 questions, 2 hours) and Psychology (about 144 questions, 2 hours). Plan on 6 to 8 weeks of study if you are finishing a degree in the subject, and 3 to 4 months if the material is not recent.
If you are preparing for the GRE General Test, see how long to study for the GRE. This page compares the three subject tests and how long each takes to prepare for.
| Test | Questions | Time | Time per question |
|---|---|---|---|
| Mathematics | About 66 | 2 hours 50 minutes | About 2.5 minutes |
| Physics | About 70 | 2 hours | About 1.7 minutes |
| Psychology | About 144 | 2 hours | Under 1 minute |
Figures are from ETS. Since September 2023, the Physics and Psychology score reports also include percent-correct scores by content area (ETS).
About 50% calculus, 25% algebra and 25% additional topics such as real analysis and discrete maths. Speed on routine calculus is the biggest factor. For a full plan, see how long to study for the GRE Math Subject Test.
The Physics test covers the standard undergraduate curriculum. ETS weights it as follows:
| Area | Share |
|---|---|
| Classical mechanics | 20% |
| Electromagnetism | 18% |
| Quantum mechanics | 13% |
| Thermodynamics and statistical mechanics | 10% |
| Atomic physics | 10% |
| Specialized topics | 9% |
| Optics and wave phenomena | 8% |
| Special relativity | 6% |
| Laboratory methods | 6% |
With under two minutes per question, the Physics GRE rewards quick estimation over full derivations: limiting cases, dimensional analysis and order-of-magnitude checks to eliminate answers. Mechanics and electromagnetism together are nearly 40% of the test, so start there. A final-year physics major can usually prepare in 6 to 8 weeks; if your coursework is older, allow 3 months and more time on quantum and statistical mechanics.
About 144 questions in 2 hours, so under a minute each, and the test is mostly recall. ETS lists approximately 30 biological, 29 cognitive, 25 measurement and methodology, 23 clinical, 19 social and 18 developmental questions. Broad coverage of an introductory textbook plus flashcards for terms and studies works better than depth in any one area. For plans, see how to study for the GRE Psychology Subject Test and how long to study for GRE Psychology.
ETS does not publish study hours for the subject tests, and the answer depends mostly on how recently you studied the field. As a planning range:
Start with a timed practice test from ETS. It shows both your starting point and whether timing will be your main problem, which it often is on Physics and Psychology.
All three tests run in the same windows. For 2026 to 2027, ETS lists September 14 to 27, 2026, October 19 to November 1, 2026, and April 19 to May 2, 2027. You can retake a subject test after 14 days. Home testing is not available in some countries, so check before you register. If you are applying in the autumn, booking September leaves room for an October retake.
All three tests reward fast recall of definitions, formulas and key results. Upload your course notes to StudyCards AI to make flashcards, export them to Anki, and review them on a spaced schedule alongside timed practice.
Try StudyCards AI Free2 hours, for about 70 five-choice questions, according to ETS. That is under two minutes per question.
Three: Mathematics, Physics and Psychology.
ETS does not publish study hours. As a planning range, allow 6 to 8 weeks if you are finishing a degree in the subject, and 3 to 4 months if the material is not recent. Take a timed practice test first to see where you stand.
In three windows a year. For 2026 to 2027, ETS lists September 14 to 27 and October 19 to November 1, 2026, and April 19 to May 2, 2027. You can retake a subject test after 14 days.
Only if your programs require or recommend one, which is most common for PhD programs in mathematics and physics. Check each program's admissions page; many no longer ask for it.
Generate Anki flashcards from PDFs