Calculate Bayes' Theorem

Probability Calculator

Free · Designed for iPad. Not verified for macOS.

Bayes' Theorem Calculator Calculate posterior probabilities with an intuitive, purpose-built calculator. Whether you're a student learning Bayesian reasoning, a clinician interpreting test results, or anyone who wants to update beliefs with evidence, this app makes it straightforward. Three Calculator Modes • Basic — Enter P(A), P(B), and P(B|A) to compute P(A|B) directly from Bayes' Theorem. • Medical Test — Input prevalence, sensitivity, and specificity to find the probability of disease given a positive or negative result. Supports both prevalence-based and positive-rate-based calculations. • Odds Form — Work with prior probability and likelihood ratios to update beliefs, ideal for sequential reasoning. Step-by-Step Breakdowns Every result includes a detailed breakdown showing exactly how each value was calculated — no black boxes. Chain Multiple Tests Use the result of one calculation as the prior for the next with a single tap. Perfect for interpreting sequential medical tests or compounding evidence. Built-In Reference Guide A comprehensive info section covers: • Key terms and definitions • Sensitivity and specificity explained • A worked medical test example with full notation • The odds form of Bayes' Theorem • How to chain tests using likelihood ratios • Key takeaways for Bayesian thinking

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    Information

    Seller
    • Kameron Young
    Size
    • 527.4 KB
    Category
    • Utilities
    Compatibility
    Requires iOS 18.6 or later.
    • iPhone
      Requires iOS 18.6 or later.
    • iPad
      Requires iPadOS 18.6 or later.
    • Mac
      Requires macOS 15.6 or later and a Mac with Apple M1 chip or later.
    • Apple Vision
      Requires visionOS 2.6 or later.
    Languages
    • English
    Age Rating
    4+
    Copyright
    • © 2026 Kameron Young
  • Privacy Policy

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