About ActuaryDeck
A formula reference and drill bank for the two entry actuarial exams, built around one conviction: a study tool that states a wrong number is worse than no study tool at all.
How the mathematics is verified
Every distribution on this site lives in a single source-of-truth module that pairs the LaTeX a page renders with a real function. On every build, a verification suite recomputes each published mean and variance numerically — summed over the support for a discrete distribution, integrated by composite Gauss-Legendre quadrature for a continuous one — differentiates each moment generating function at zero, and accumulates each density to check the published CDF. A typo in a printed formula fails the build.
The same applies to the questions. 330 of the 400 questions state a numeric answer, and each carries a closure that recomputes it from the shared primitives. The suite asserts both that the recomputation matches the stated answer and that the stated answer is the number the correct option actually prints.
What is free and why
All 58 formula pages are free forever, with no account. The formulas are public knowledge, the derivations belong on the open web, and those pages are how candidates find this site. What is paid is repetition: the full question bank, the per-topic drills, the timed rounds and the complete recall deck.
Positioning
ActuaryDeck is a supplement, not a replacement. Keep your ADAPT subscription for the home stretch — use this to drill formulas and problem patterns for a fraction of the price.
There is no adaptive difficulty engine here and no readiness score, because building one honestly needs a scale of candidate response data this site does not have. Pretending otherwise would cost more trust than the sale is worth — see the guide on what those ratings actually measure.
Contact
Corrections, questions, or a formula you want covered: support@actuarydeck.app. Reported errors get fixed.