# Free 120: USMLE Step 1 and Step 2 CK Sample Items > What is the Free 120? The Free 120 is the free set of official USMLE practice questions on usmle.org: 119 sample items for Step 1 and 120 for Step 2 CK, each with an answer key and an interactive version that mirrors the real test software. It is written by the board that writes your exam. ## The two sets ### Step 1 - Page: https://www.stepgenie.app/free-120/step-1 - Official sample questions page: https://www.usmle.org/exam-resources/step-1-materials/step-1-sample-test-questions - Official PDF: https://www.usmle.org/sites/default/files/2021-10/Step_1_Sample_Items.pdf - Official interactive testing experience: https://www.starttest.com/custom/usmle/?stpf1 - Items: 119. Explanations published: 3. Built from the Step 1 sample-items booklet marked "updated April 2026", the PDF linked from the official Step 1 sample-questions page. ### Step 2 CK - Page: https://www.stepgenie.app/free-120/step-2-ck - Official sample questions page: https://www.usmle.org/exam-resources/step-2-ck-materials/step-2-ck-sample-test-questions - Official PDF: https://www.usmle.org/sites/default/files/2021-10/Step2_CK_Sample_Questions.pdf - Official interactive testing experience: https://www.starttest.com/custom/usmle/?stpf2 - Items: 120. Explanations published: 3. Built from the Step 2 CK sample-questions booklet linked from the official Step 2 CK sample-questions page, read on 2026-09-05. The cover is marked "updated July 2023"; usmle.org re-uploaded the file on 2025-08-25 (its Last-Modified header), so treat the cover date as the edition and re-check the item numbering if the file changes again. ## Scoring The sample items come with an answer key but no score report and no official percent-to-three-digit conversion. Percent correct on the Free 120 is not a predicted score. The exams that do publish an official conversion are the NBME self-assessments. Convert one at https://www.stepgenie.app/tools/nbme-score-converter. --- Canonical page: [Free 120](https://www.stepgenie.app/free-120)