Drake equation explorer

What you are seeing: the Drake equation $N = R_\star \cdot f_p \cdot n_e \cdot f_l \cdot f_i \cdot f_c \cdot L$ visualized as a multiplicative chain of probabilities and a Monte Carlo histogram over their uncertain ranges. Each slider sets the log-range of one factor; 2000 trials draw log-uniformly from those ranges and the histogram shows the distribution of $N$ across 20 decades.

The Carroll-Ostlie reference values give $N \approx 30$ (lots of civilizations); pessimistic intelligence and signal-lifetime factors collapse $N$ below 1. The Fermi paradox is the gap between the optimistic central value and our observed lack of detections.