Statistical Library

Normal Distribution in Google Sheets

The bell curve that powers every financial forecast.

Interactive Sandbox

10,000 simulations running live in your browser.

Base Value 100
6582.5100117.5135
P10 Worst Case 87
P50 Median 100.2
P90 Best Case 113

When to use it

The Normal (Gaussian) distribution models uncertainty around a known mean — your best estimate — with a standard deviation that captures how wide your confidence interval is. It's symmetric, so upside and downside risk are treated equally. Use it whenever you have historical data that clusters around an average: revenue growth rates, cost variances, or process cycle times.

  • Revenue and expense variance modeling in FP&A
  • Manufacturing tolerance and quality control (Six Sigma)
  • Portfolio return distributions in finance
  • Performance benchmarking with well-understood averages

How to build it

Native Sheets Formula

=NORM.INV(RAND(), mean, stdev)

Using native RAND() requires you to copy this formula 10,000 times manually, which severely lags the browser.

The MonteSheet Way

MonteSheet uses a local browser engine to run 100,000 iterations in 4 seconds without writing a single formula.