Free tool · High Yield Board Prep
Know where you stand.
In 60 seconds.
Plug in your NBMEs, UWSAs, and UWorld numbers. Get the exact pass-probability the NBME uses internally, with every calculation, weight, and decay factor shown in full.
Step 01
Your target test date
Step 02
NBME scores
Forms 25 through 31. Enter the equated percent correct from your CBSSA score report.
No NBMEs added yet. Click + Add NBME above.
Step 03
UWSA scores
UWorld Self-Assessments 1, 2, and 3 (3-digit simulated score).
Optional. Add any UWSA scores you have.
Step 04
UWorld (optional)
Directional signal. Weighted at 1/4 of an NBME because it measures content in a different question style.
Results
Add a test date and 2 practice-exam scores to see your prediction.
Full transparency
How we calculated your prediction
Everything is shown. There is no black box. You can see exactly how each of your scores was weighted, how much time decay costs, and the literal formula.
Signal hierarchy
Why each signal is weighted the way it is
The math gives the heaviest weight to what correlates strongest with your real Step 1 outcome.
| Source | Weight | Why |
|---|---|---|
| NBME CBSSA (25 through 31) | 100% | Equated percent-correct on real NBME forms. Same item bank the NBME calibrates Step 1 against. Strongest single predictor. |
| UWSA 1 / 2 / 3 | 100% | UWorld Self-Assessments output a simulated 3-digit score calibrated against NBME data. Accepted at parity with NBME. |
| UWorld first-pass % | 25% | Measures content knowledge but in a different question style (longer vignettes, more distractors). Directional signal only. |
| UWorld tutor mode % | 12.5% | Untimed with immediate feedback. Inflates performance relative to timed conditions. |
| UWorld second-pass % | 10% | You have seen the questions before. Memory contaminates the signal. |
Time decay
How time factors in
Older scores count for less. We multiply each input by 0.987527 per day of age. This is the published NBME decay constant.
| Age of the score | Weight | Visualized |
|---|---|---|
| Taken today | 100% | |
| 1 week ago | 92% | |
| 2 weeks ago | 84% | |
| 1 month ago | 69% | |
| 2 months ago | 47% | |
| 3 months ago | 32% |
Practical takeaway: an NBME you took 30 days ago carries about 69% of its face value. A 90-day-old score only 33%. Want a tighter prediction? Take a fresh NBME.
The formula
The math, in plain language
- Each score is converted to a 3-digit Step 1 equivalent using the NBME published conversion table.
- Older scores are weighted less using NBME's decay constant of 0.987527 per day.
- Your weighted-average current level is projected forward to test day using NBME's own study-period projection curve (scores drift toward 292 under continued study).
- For Step 1, a logistic function calibrated to NBME's published pass-probability anchors (64% equated = ~92% pass, 68% = ~97%, 70% = ~99%) converts the projected score into a pass probability.
- The 95% confidence interval reflects an 8-point standard error on a single practice exam, widened by any variance between your inputs.
Sources
Privacy
Your scores never leave your browser until you click "email me the audit." We do not store your data on our servers.