USMLE Step 2 CK (Clinical Knowledge) tests the clinical science and patient-care knowledge needed to practice under supervision. It is delivered in sixteen 30-minute blocks over a 9-hour session, with a passing standard of 218. This guide covers eligibility, applying, format, content, scoring, rules and preparation. Facts come from usmle.org, read on October 31, 2026.
Step 2 CK at a glance
| Element | Exams on or after May 7, 2026 | Before May 7, 2026 |
|---|---|---|
| Blocks | Sixteen 30-minute blocks | Eight 60-minute blocks |
| Questions per block | No more than 20 | No more than 40 |
| Testing session | One 9-hour session | One 9-hour session |
| Minimum break | 55 minutes | 45 minutes |
| Optional tutorial | 5 minutes | 15 minutes |
| Passing standard | 218 for exams on or after July 1, 2025 | |
Eligibility and applying
- Eligibility categories match Step 1: an LCME-accredited MD program, a COCA-accredited DO program, or an eligible school outside the U.S. listed in the World Directory of Medical Schools as meeting ECFMG eligibility requirements. You must meet this when you apply and on exam day.
- U.S. students and graduates apply through NBME (MyUSMLE); those from schools outside the U.S. apply through FSMB.
- The listed fee for 2026 and 2027 is $695, with a regional fee ($235 as listed) for exams taken outside the U.S. and Canada. Fees can change.
- International graduates should also read the ECFMG guide; ECFMG certification is separately required for Step 3.
What Step 2 CK tests
The Step 2 CK outline groups questions by clinical science and by physician task. Percentages are subject to change at any time.
| Clinical science | Share |
|---|---|
| Medicine | 55-65% |
| Pediatrics | 17-27% |
| Obstetrics and gynecology | 10-20% |
| Psychiatry | 10-15% |
| Surgery | 5-15% |
| Task | Share |
|---|---|
| Diagnosis | 16-20% |
| Laboratory and diagnostic studies | 13-17% |
| Mixed management | 12-16% |
| Pharmacotherapy | 8-12% |
| Clinical interventions | 6-10% |
| Health maintenance and disease prevention | 5-10% |
| Prognosis and outcome | 5-9% |
| Systems-based practice and patient safety; professionalism | 5-7% each |
| Practice-based learning and improvement | 3-5% |
| Area | Share |
|---|---|
| Nutrition | 15-20% |
| Social sciences: legal and ethical issues, professionalism, systems-based practice and patient safety | 10-15% |
| Renal and urinary, and reproductive | 7-13% |
| Cardiovascular | 6-12% |
| Musculoskeletal, skin and subcutaneous | 6-12% |
| Behavioral health | 5-10% |
| Blood and lymphoreticular/immune | 5-10% |
| Gastrointestinal | 5-10% |
| Nervous system and special senses | 5-10% |
| Respiratory | 5-10% |
| Multisystem processes and disorders | 4-8% |
| Endocrine | 3-7% |
| Pregnancy, childbirth and the puerperium | 3-7% |
| Biostatistics, epidemiology/population health and interpretation of medical literature | 3-5% |
| Human development | 2-4% |
See high-yield topics and biostatistics for the USMLE.
Scoring
The passing standard is 218 for exams administered on or after July 1, 2025. USMLE reviews standards about every four years, so confirm the number before you rely on it. See USMLE passing scores and results, rechecks and transcripts for score release timing.
Rules that apply
- Attempt limits and waiting periods: attempts and retakes.
- State time limits for completing the Steps: the seven-year rule.
- Check-in, ID and accommodations: exam security and accommodations.
Preparation roadmap
This is a study suggestion, not official guidance.
- Anchor on clinical rotations. Because medicine is the largest share, rotation learning carries much of the exam.
- Use a QBank early. Practice in mixed, timed blocks, such as with UWorld or AMBOSS, and review every explanation.
- Cover management as well as diagnosis. Several of the largest task areas are about management, tests and drugs, not just naming a disease.
- Check readiness. The NBME CCSSA gives an estimated probability of passing Step 2 CK, which NBME says is not a guarantee.
- Practice stamina. A 9-hour day has sixteen blocks; rehearse several in a row. See pacing for 30-minute blocks and break planning.
Step 2 CK and residency
Step 2 CK is commonly taken before the application season. Time your exam so results are available when programs review applications, and check each program's requirements. Our NRMP Match guide lays out the calendar.
See also the complete Step 1 guide, the complete Step 3 guide, the complete USMLE guide and the Step 2 CK exam page.