NBME Score Calculator: Predict Your USMLE Step Score in Seconds
Enter any combination of NBME, UWSA, Free 120, AMBOSS, or CMS Form scores. Get a point estimate, 95% confidence interval, and percentile — instantly. No signup.
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Add your scores. See your range instantly. No signup.
We don't store your scores unless you save. Free, no signup.
How the NBME calculator works
Four steps, under sixty seconds. The calculator runs entirely in your browser — your scores never leave your device unless you save them to an account.
Pick your Step exam
Step 1 (Pass/Fail), Step 2 CK (numeric), or Step 3.
Enter your practice scores
Add up to 10 scores from any source: NBME, UWSA, Free 120, AMBOSS, or CMS forms.
Set your test date
We weight more recent scores higher and apply a recency-decay model.
Get your prediction instantly
Point estimate + 95% confidence interval + percentile + pass probability.
Every practice score you have — supported
Mix and match sources. Each source has its own adjustment baked in, so you don't have to do mental math.
NBME 28, 29, 30, 31, 32
Most accurateAll current and recent NBME forms supported. Score range: 200-280.
UWSA 1 & UWSA 2
Auto-adjustedAuto-adjusted by −3 points (UWSAs run hot). UWSA 2 is more predictive.
Free 120
Best signalEnter % correct (0-100). The single most predictive form for Step 2.
AMBOSS Self-Assessment
Auto-adjustedScore range 0-100. Inflation correction applied automatically.
CMS Form (subject)
Subject-levelPer-subject scores for Step 2 CK. Best for finding weak rotations.
Old NBMEs (1-26)
Use cautiouslyAllowed but flagged — typically under-predict by 3-5 points.
Why this calculator beats the alternatives
Most online NBME calculators were built in 2019 and have not been updated since Step 1 went pass/fail. Here is what makes ours different.
| Feature | NBMEcalc | Older calculators |
|---|---|---|
| Free unlimited use | ✓ | — |
| Multiple input sources (NBME + UWSA + Free 120 + AMBOSS) | ✓ | — |
| 95% confidence interval | ✓ | — |
| Per-subject weak-spot detection | ✓ | — |
| Recency-weighted aggregation | ✓ | — |
| Modern UI (mobile + desktop) | ✓ | — |
| Pass probability for Step 1 P/F | ✓ | ✓ |
| Optional PDF report ($14.99) | ✓ | — |
| Open conversion methodology | ✓ | — |
Your scores never leave your browser
The calculator runs entirely client-side. We only store data if you create an account and click Save prediction. Even then, predictions are stored encrypted and only ever visible to you. See our privacy policy for details.
Frequently asked questions
How does the NBME score calculator work?+
Enter the scores you have so far. Our calculator runs each through a piecewise linear regression fit to 1,247 paired NBME ↔ Step 2 CK outcomes, applies a source adjustment (UWSAs −3, AMBOSS −5, etc.), then aggregates with recency weighting. The output is a point estimate plus a 95% confidence interval.
Is the calculator really free?+
Yes. Anonymous predictions, the confidence interval, and the percentile ranking are 100% free. You only pay if you want to download a PDF study report ($14.99 one-time) or unlock the Pro dashboard ($9.99/mo).
How many practice scores should I enter?+
At least 3, ideally 5-7. The calculator's confidence interval narrows from ±12 points (1 score) to ±4 points (5+ scores). More inputs = a sharper prediction.
Why is my predicted Step 2 CK score lower than my latest NBME?+
NBME forms typically under-predict your real Step 2 CK score by 3-8 points. If you scored 240 on NBME 32 last week, our calculator should output a Step 2 CK estimate near 250 — that gap is normal.
Does the calculator work on mobile?+
Yes. Optimized for iPhone, Android, and tablet. You can also install NBMEcalc as a Progressive Web App (PWA) for offline access.
Ready to know where you stand?
The calculator is right above. Enter your latest scores in under a minute. If you want a printable PDF report with a 14-day study plan, upgrade for a one-time $14.99.