How Predictive Is Free 120 for Step 1?
Free 120 has been submitted to Predict My Step Score 79,020 times and tracked against the real Step 1 results students went on to report. In that data, Free 120 was a useful pass signal — clearly ahead of a coin flip.
What is Free 120?
The Free 120 (Free 137 for Step 3) is the USMLE's own free set of sample questions, published to show what the exam interface, question style and pacing feel like. It reports a raw percentage correct, not a scaled score, and was never built as a score predictor — but because the questions come from the exam's authors, many students treat it as a final checkpoint.
What is a good Free 120 score?
In our data, Free 120 scores ranged from 39% to 99%. Since Step 1 is pass/fail, there is no target number to hit: a "good" Free 120 score is one that sits comfortably inside the range where passing was the norm for students in our data, with enough margin that one rough block on the day would not put you at risk.
When should you take Free 120?
Take it in the final week, mainly to rehearse the real interface and pacing, and treat the percentage as a floor rather than a forecast.
Does it matter when you take Free 120?
Timing matters twice over. First, a score from six weeks out is a snapshot of a student who then kept studying, so early tests tend to sit below the real result — much of what looks like "underprediction" is simply improvement after the test. Second, our predictor does not treat every score you enter equally: each one is weighted by the exam's R² and by how recently you took it, with a recency factor that decays exponentially from your most recent test back to your oldest, and your three most recent scores drive the final adjustment. Enter the days-before-exam for each test honestly — it changes the answer.
Enter your Free 120 score
How Free 120 compares
Wondering whether to take Free 120 next? See which practice tests are most predictive.
| Rank | Practice exam | Predictive power |
|---|---|---|
| 1 | UWSA 1 | High |
| — | Free 120 | Moderate |
| 2 | Practice exam | — |
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Some Step 1 practice tests predict a pass barely better than a coin flip. Don't find out which ones on exam day.
Unlock the full ranking + your predicted scoreFrequently asked
Is Free 120 accurate?
In our data Free 120 was a useful pass signal — clearly ahead of a coin flip. No single practice test settles pass/fail on its own, though — combining your scores, weighted by each exam's track record and timing, gives a much better read than any one sitting. Predict your Step 1 score →
Does Free 120 overpredict or underpredict Step 1?
Step 1 is pass/fail, so there is no point bias to report. In our data Free 120 was a useful pass signal — clearly ahead of a coin flip.
Is Free 120 or UWSA 1 more predictive?
UWSA 1 is more predictive in our data. The exact gap is part of the full ranking, which is available to premium users.
Where does this data come from?
79,020 Free 120 scores have been submitted to Predict My Step Score so far. Whenever a student also reports their actual Step 1 result, the pair goes into the model behind this page; it was last refit on 2026-05-14.
Can't I just ask ChatGPT how predictive Free 120 is?
Not reliably. A prediction is only as good as the paired data behind it: real Free 120 scores matched to the real Step 1 result those same students went on to get. General-purpose AI models are trained on forum posts and articles, not on verified outcomes, so what you get back is a summary of anecdotes rather than a calibrated estimate. The numbers on this page come from students who reported both. Read more →
Free 120 alone gives you a blurry answer. Your full set of scores gives a sharp one.
The predictor combines every practice exam you have taken — weighted by how predictive each one is and how recently you took it — into a single prediction with a 95% confidence interval.
Predict my Step 1 scorePremium adds the full ranking, unlimited predictions, and tracking over time.
Data refreshed 2026-05-14.
