In ERPNext, default precision for
Percent field is three. It allows you to enter value having value upto three decimal places.
You can also change/customize the precision settings globally or for a specific field.
To change the precision globally, go to:
Setup > Settings > System Settings.
You can also set field specific precision. To do that go to
Setup > Customize > Customize Form and select the DocType there. Then go to the specific field row and change precision. Precision field is only visible if field-type is one of the Float, Currency and Percent.