I am posting here just to document a rather unimportant bug and suggest a documentation change. The bug: Precision to the right of the decimal place does not go out to a maximum of 10,000 places, but effectively out to only 4,089 (? - weird number) places. Following is a very simple batch file that can be used to verify this: @Echo Off SetLocal Set Precision=4080 Do Forever Set Var=%@Eval[1/6=1.%Precision] @Echo Precision: %Precision Set Precision=%@Inc[%Precision] EndDo EndLocal Quit 0 I would suggest as a simple workaround that you just change the documentation to show exactly what precision is actually available under exactly what circumstances (I've noticed that one can go higher than this in some relatively unimportant cases), rather than changing the program source code (although you can certainly do that if you want! ; > ).