About 1 in 10 people use the same four-digit PIN, based on an analysis of Have I Been Pwned? data by Julian Fell and Teresa Tan for ABC News:
Even though there are 10,000 possible combinations, when humans get involved that equation changes dramatically.
If someone wants to unlock a stolen phone – or retrieve money from an ATM – and only have five guesses, this data suggests they still have a one-in-eight chance of guessing correctly.
The scroll through the heatmap of PIN numbers, which shows the first two digits on the vertical axis and the last two digits on the horizontal, drives the point home. Maybe stay away from the diagonal and horizontal lines.
