Benford’s law

Benford’s law (single and double digits)

First Digit Law : Percentage of time digits 1 through 9 are expected to occur in the first position in a genuine data set of numbers.

First Two Digits Law : Percentage of time digits 10 through 99 are expected to occur in the first two positions in a genuine data set of numbers.

How to use it ?

If an employee is committing fraud by producing fraudulent invoices, the amounts are not generated radomly, employee has to create a ficticious amount. These amounts can become outliers in Benford’s law affecting expected frequencies for each first/first-Two digit(s) of the invoice amount.

What does our fraud detection analytics software do?

We run more than a dozen separate tests with just the basic data. In fact over half the test for employee, payroll, accounts payable, check, and business fraud are run with just check data, check amount and payee. Here are the tests we run:

Benford’s law

single and double digits

Similar vendors

(you set the similarity percentage)

Non-business day transaction

(US Holidays included)

Under cut-off amounts

(you set the limits)


(also helps identify vendors putting stress on the business)

Fictitious vendor search

(you select the search words like PO Box, or consultant)

Amounts Exactly Twice

As much as other

Amounts starting with

Same First Four Digits