How We Calculate Your Pass Probability

Honest, auditable math. Here's exactly what goes into the number on your dashboard.

Pass probability — the inputs

Every number comes from your own activity on PrepLion. Specifically:

  • Per-unit mastery scores from your practice sessions
  • Diagnostic scores as a baseline when no practice data exists yet for a unit
  • Best mock exam score (any full-length mock you've taken)
  • Recent 14-day accuracy across all completed sessions
  • Total sessions + total questions attempted — these drive our confidence tag (low / medium / high)

We weight mastery most heavily (~50%), recent accuracy next (~30%), and mock performance last (~20%). The final number is capped at 95% — no prediction is perfect, and we'd rather underpromise.

Improvement projections — the model

When we tell you "in 7 days you'll be at ~60%," here's how we got that number:

  • Baseline daily gain: ~3 pass-points per day for a motivated student practicing 30+ questions.
  • Diminishing returns: every 10 points of gain cuts the next day's rate by ~25% (easier to go from 30 to 40 than from 70 to 80).
  • Ceiling: 95%. Same cap as the main pass-probability calculation.

This projection is intentionally conservative. Students who practice more aggressively — 50+ questions a day, daily review, weak-unit drilling — beat the curve. Students who practice sporadically underperform it.

Pass Confident Guarantee — the fine print

If PrepLion shows you a pass probability of 80% or higher and you don't pass the real exam, we extend your subscription by 60 days free and refund your most recent plan payment.

Conditions: the 80%+ must have been shown to you within the 14 days preceding your exam date, confirmed by at least one full mock exam. Email your exam score report to [email protected] within 30 days of the exam.

Plus 7-day money-back guarantee on every plan — email support within 7 days of purchase, no questions asked.

Why we're transparent about this

Most prep sites make promises they can't measure and can't back. We tell you the inputs because they're your data, they're on your dashboard, and they're auditable. If a projection misses, you'll see it immediately — we don't hide bad numbers.

Questions? Email [email protected].

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