DEFINITION of 'Fat Finger Error'
A human error caused by pressing the wrong key when using a computer to input data. Fat finger errors are often harmless but can sometimes have significant consequences for example, if the wrong number is entered in performing a mathematical calculation.
BREAKING DOWN 'Fat Finger Error'
In the aftermath of the May 6, 2010, "flash crash" that caused a significant, rapid and unexpected drop in the Dow, one possible early explanation was fat finger error. The idea was that a trader had entered an order incorrectly, placing the order in the billions rather than the millions. In reality, such trading errors are unlikely because of safeguards implemented by brokerages and exchanges.