Created by Multiverse Hacking, 2025. MultiverseHacking.com.
What this is: A Drake-Equation–style calculator for simulation hypotheses. It estimates the chance that a randomly chosen world (universe) is base versus simulated. You set how many simulation-capable civilizations there are per base universe (C), the percentage that actually run simulations (f_run), how many simulations each running civ creates in the next layer (k), and how nesting works. For nesting, choose either a fixed maximum depth d, or a probabilistic mode where each simulation is allowed to spawn the next layer with probability p_allow. In probabilistic mode the key quantity is m = k · p_allow (the mean branching factor). If m ≥ 1 and infinite nesting is allowed, the expected number of simulated worlds diverges and the probability of a base world goes to zero.
How to read the outputs: S is the expected number of simulated worlds per running civilization. C · (f_run/100) · S is the expected sim-to-base world ratio. P(base world) and P(sim world) are the probabilities for a random world; we also show Odds as “1 in N.” The lines for m and the threshold p_allow* = 1/k indicate whether you are below or above the branching point; near that threshold, probabilities can shift dramatically.
S = k + k^2 + ... + k^d = k(1-k^d)/(1-k) (or S=d if k=1)p_allow, mean branching m = k·p_allow.S = k · (1 - m^D)/(1 - m) (or S=kD if m=1)S = k/(1 - m) if m < 1; diverges if m ≥ 1.
P(base\ world) = 1 / (1 + C · (f_run/100) · S)