How to use Excel to validate a dataset according to Benford’s Law

Benford’s Law describes the phenomenon that in a large dataset, the leading digit of each number does not occur with the intuitively expected probability of 1:9 (11.1%), but rather with a much larger probability for the smaller numbers. For more details on Benfords’s Law, you can read the Wikipedia Article about it, but keep on reading here if you want to learn how to use Excel to check if a dataset is consistent with it. It’s very easy!

For this example I have used population data for all the counties of the United States from


Yellow pop-up box when selecting cell in Excel


Wouldn’t it be cool if you could have a yellow info note that pops up when you select the cell in Excel? Actually you can! Let’s look at a little used feature of Data Validation.

It’s easy and you can do it in less than a minute!