USMLE Step 2 CK · 737 questions
USMLE Step 2 CK question bank
Argonaut's Step 2 CK bank has 737 exam-style questions across 19 organ systems, with every answer choice explained and every question approved by a clinician. Practice in tutor or timed mode, in 20-question blocks that match the 2026 exam. Full access is $48 once and covers Step 1 too.
No account needed for the free questions.
At a glance
The Step 2 CK bank in numbers
Counts come straight from the live bank and update as questions are added.
- Questions
- 737
- Organ systems
- 19
- Topics
- 420
- Format
- Single best answer
- Explanations
- Every answer choice
- Review
- Clinician-approved
- Modes
- Tutor and timed
- Timed pace
- 90 s per question
- Default block
- 20 questions · 30 min
- Free to try
- 52 questions, no account
- Price
- $48 once, both exams
- Expires
- Never
Who it's for
- Third- and fourth-year students preparing for Step 2 CK alongside or after their clerkships.
- Students who want more clinical-decision practice on top of their main bank.
- International medical graduates preparing for Step 2 CK on a budget.
Coverage
Built for clinical decisions
Step 2 CK is scored, and it tests what you would do for the patient in front of you: the most likely diagnosis, the best next step, the test to order, the drug to start and what to screen for.
Medicine is the largest clinical science on the official outline (55–65% of items), followed by pediatrics (17–27%), obstetrics and gynecology (10–20%), psychiatry (10–15%) and surgery (5–15%). Argonaut's Step 2 CK questions are written for those decisions, not adapted from Step 1.
| System | Share | Questions |
|---|---|---|
| General Principles | 2 | |
| Human Development | 22 | |
| Immune | 16 | |
| Hematology | 34 | |
| Behavioral Health | 62 | |
| Nervous & Special Senses | 51 | |
| Dermatology | 31 | |
| Musculoskeletal | 28 | |
| Cardiovascular | 77 | |
| Respiratory | 59 | |
| Gastrointestinal | 54 | |
| Renal & Urinary | 26 | |
| Pregnancy & Childbirth | 41 | |
| Female Reproductive & Breast | 36 | |
| Male Reproductive | 9 | |
| Endocrine | 46 | |
| Multisystem | 18 | |
| Biostatistics & Epidemiology | 28 | |
| Social Sciences & Ethics | 97 |
Content shares from the official USMLE Step 2 CK content outline, checked 11 October 2026.
Try one now
A real Step 2 CK question, explained
This is one of the 52 free Step 2 CK questions, exactly as it appears in the bank: cardiovascular, mitral valve prolapse.
A 24-year-old woman is evaluated after a murmur is heard during a routine examination. With her supine, auscultation reveals a midsystolic click followed by a late systolic murmur at the cardiac apex. When she stands, the click occurs earlier, and the murmur becomes longer and louder.
Which of the following is the most likely diagnosis?
Show the answer and explanation
Answer: C. Mitral valve prolapse
A midsystolic nonejection click followed by a late systolic murmur is characteristic of mitral valve prolapse. Standing reduces preload and ventricular size, causing prolapse to occur earlier in systole; accordingly, the click and murmur move closer to S1, and the murmur lengthens and often becomes louder. Although hypertrophic obstructive cardiomyopathy can also produce a louder murmur with standing, its typical midsystolic ejection murmur lacks this click–late systolic murmur pattern.
Why each answer choice is right or wrong
- A
Aortic stenosis. Aortic stenosis produces a systolic ejection murmur rather than a click followed by a late systolic murmur. Its murmur also tends to become quieter with standing.
- B
Hypertrophic obstructive cardiomyopathy. The murmur of hypertrophic obstructive cardiomyopathy can become louder with standing, making it a plausible alternative. It is typically a midsystolic ejection murmur, however, not a late systolic murmur preceded by a midsystolic click.
- C
Mitral valve prolapse (correct). Mitral valve prolapse: click and late systolic murmur shift earlier and lengthen with reduced preload
- D
Physiologic flow murmur. A physiologic flow murmur would not account for the midsystolic click followed by a late systolic murmur that shifts earlier and lengthens with standing.
- E
Mitral regurgitation. Mitral regurgitation typically causes a holosystolic murmur, rather than the click and late systolic murmur heard here. The characteristic change in click timing with standing supports mitral valve prolapse.
Educational objective
Recognize mitral valve prolapse from a midsystolic click followed by a late systolic murmur. Reduced preload with standing causes the click and murmur to occur earlier, distinguishing this pattern from other dynamic systolic murmurs.
Study the concept: Mitral valve prolapse (free Library chapter)
How practice works
Test-day conditions, or learn as you go
Tutor mode
See the answer and the full explanation after each question. Best for learning a system for the first time.
Timed mode
90 seconds per question, explanations after the block. Default blocks are 20 questions in 30 minutes, like the real exam.
Real exam tools
Highlighter, strike-out, lab values, calculator, notes and marking, on a screen laid out like test day.
Your own blocks
Filter by exam, system, discipline and topic, or by unused, incorrect and marked questions. Up to 40 per block.
The Step 2 CK format
What the 2026 Step 2 CK looks like
Since 7 May 2026, Step 2 CK uses new test software with shorter blocks. Content and scoring did not change.
- Questions
- 316
- Blocks
- 16
- Questions per block
- 18 to 20
- Minutes per block
- 30
- Exam day
- 9 hours
- Before
- eight 60-minute blocks of 38 to 40 questions
How Argonaut matches it: timed mode runs at 90 seconds a question and defaults to 20-question blocks, so one Argonaut block is one exam block. Within a block you can move between questions and change answers; explanations appear when the block ends.
Read the full 2026 format guideSource: USMLE test delivery software update, checked 11 October 2026.
ARGO
Practice that follows your weak spots
Optional, included in Full access, and easy to ignore if you prefer to build your own blocks.
- 01
Measure
ARGO logs 16 data points on every answer: right or wrong, time, confidence, changed answers, the distractor that pulled you in, and how long since you last saw the topic.
- 02
Rank
It works out which Step 2 CK topics cost you the most points, separating gaps from misconceptions, second-guessing and forgetting.
- 03
Fix
Each ARGO session mixes new questions on your weakest topics, drills on concepts you confuse, and spaced retests of questions you missed.
Quality
Who writes the questions
Each question is written to the NBME Item-Writing Guide. A clinician reviews the facts, the keyed answer and every explanation, and approves it before it goes live.
- One best answer, a full clinical vignette, and no negatively worded or trick lead-ins.
- Answer choices of the same kind and length, so test-taking tricks don't work.
- Duplicates of an existing question are caught before import.
- Students can flag any question from the explanation, and every report is read.
Free and paid
What's free, and what $48 adds
Free
- 52 Step 2 CK questions with full explanations, no account
- The Daily Challenge, every day
- Free Library chapters
- Basic stats with a free account
Full access, $48 once
- All 737 Step 2 CK questions, plus the Step 1 bank
- The full high-yield Library
- ARGO sessions and full analytics
- Nuggets, flashcards and a notebook
One payment, no renewal and no expiry date: "lifetime" means for as long as Argonaut runs the service, as our terms define it. Full refund within 14 days if you've answered fewer than 200 questions (refund policy). The optional question-writing add-on is $4.99 a month.
By subject
Practice Step 2 CK by subject
Each subject page lists the topics the bank covers, with free questions to try.
- Step 2 CK internal medicine questionsOfficial outline: Medicine (clinical science), 55–65% of the exam
- Step 2 CK OB/GYN questionsOfficial outline: Obstetrics & Gynecology (clinical science), 10–20% of the exam
- Step 2 CK psychiatry questionsOfficial outline: Psychiatry (clinical science), 10–15% of the exam
- All free Step 2 CK questions52 questions with full explanations, no account neededFree
Step 2 CK questions, answered.
01How many questions are in Argonaut's Step 2 CK question bank?
737 as of 12 November 2026, across 19 organ systems and 420 topics. We count only published bank questions; practice questions ARGO writes for one student aren't included.
02Does Argonaut match the new 2026 Step 2 CK format?
Since 7 May 2026, Step 2 CK has 16 blocks of 18 to 20 questions, 30 minutes each. Argonaut's timed mode gives 90 seconds per question and starts at 20-question blocks, so a block takes the same 30 minutes. See the 2026 exam format.
03How is Step 2 CK practice different from Step 1?
Step 2 CK questions put you in charge of the patient: what to do next, which test to order, which treatment to start and when to refer. Our Step 2 CK questions are written for those decisions, with every answer choice explained.
04Can I try the Step 2 CK bank before paying?
Yes. 52 Step 2 CK questions are free to answer without an account, with full explanations: free Step 2 CK questions.
05Does one purchase cover Step 1 too?
Yes. $48 once unlocks the Step 1 and Step 2 CK banks, the full Library and ARGO, with no expiry date. See pricing.
06Who writes the questions?
Each question is written to the NBME Item-Writing Guide and reviewed and approved by a clinician before it goes live. Read our editorial policy.
07How does ARGO help with Step 2 CK?
It tracks your accuracy, timing and confidence by system and topic, then builds each session around the topics costing you the most points, with spaced retests of questions you missed. How ARGO works.
Start your Step 2 CK prep today.
Answer the free Step 2 CK questions now. When you're ready, $48 once unlocks every question for Step 2 CK and Step 1.
$48 · once · Step 1 + Step 2 CK