A venture fund simulator.
Describe a fund — its size, the number of investments, the failure rate, the shape of the right tail — and we run 10,000 simulated versions of that fund. The histogram shows the full distribution of plausible outcomes, not just the headline number on a pitch deck.
Fund TVPI — distribution across 10,000 simulated funds
Each bar = the % of simulated funds that landed in that TVPI bucket. Quantile markers (p10–p90) overlaid in white.
Where the return came from
Averaged across all simulated funds. The fewer winners drive the return, the more the math is power-law shaped.
Explore
Six scenarios. Each loads a preset and a short argument. Disagree freely.
Methodology — what's actually being simulated +
The model
Each company independently draws an outcome multiple from a mixture distribution: with probability loss rate it returns 0; otherwise it draws from a Pareto distribution with shape α, lower bound 1, truncated at tail cap. Pareto is the standard parametric form for venture outcomes — it produces the long tail empirical fund data shows.
Sampling
Survivor sampling: u ~ Uniform(0, U_max) where U_max = 1 − (1 / tailCap)^α, then x = 1 / (1 − u)^(1/α). Truncating at tail cap bounds the largest possible outcome. With α near 1 the tail is fat and a single 100x outcome dominates; with α near 3 the tail collapses and the distribution looks almost normal.
Fund economics
Initial check = (1 − reserves) × fundSize / N. Follow-on capital is split across the portfolio according to your selected strategy (pro-rata = equal split; super pro-rata = top 30% of winners by realized multiple; none = reserves returned to LPs at 1.0x). Gross return is summed across all positions and scaled by the ownership multiplier. We subtract management fees over the fund life and apply carry on profits above 1.0x of committed capital. The reported TVPI is net to LP.
Calibration
Seed preset (α=1.5, loss rate 65%, cap 100x) is consistent with public empirical work — Correlation Ventures, Kauffman, AngelList. Series A and Growth presets shift loss rate down and tail thickness up, matching the conventional view that later stages have lower variance.
Limitations (read these)
- Company outcomes are assumed independent. They aren't — vintage years, sector concentration, and macro shocks correlate failures. Real fund TVPI variance is wider than this model shows.
- Outcomes are net of dilution. The Pareto sample represents what your initial check became at exit. Cap-table mechanics are folded into the distribution, not modeled separately.
- Time is collapsed. The simulation reports TVPI, not DPI, and treats the fund life as a single horizon. Time-value-of-money matters for IRR but not for the visceral point this lab is making.
- This is a teaching tool. Don't use it to underwrite a manager. Use it to argue with their pitch deck.