Available with Spatial Analyst license.
Overview
Finds the remainder (modulo) of the first raster when divided by the second raster on a pixelbypixel basis.
Notes
The order of the inputs are important, since they affect the output result.
Mod assumes both its inputs are integers. If any inputs are not integer, those inputs will be converted to integers through truncation. Output values are always integers.
Any value modulated (divided) by 0 is assigned NoData in the output. Therefore, any location on the second input that is either 0 or NoData will return NoData for that location on the output.
If the second input value (the divisor) is larger than the first input value (the dividend), the output will be the same value as the first input. For example, if you were to divide a value of 8 by the value 10, the integer division calculation will return the input value 8 for the remainder.
Parameters
Parameter name  Description 

Raster  The numerator input. A constant value can be used as an input for this parameter, provided a raster is specified for the other parameter. 
Raster2  The denominator input. A constant value can be used as an input for this parameter, provided a raster is specified for the other parameter. 
Extent Type  Choose which extent should be used in the output raster:

Cellsize Type  Choose which cell size to use in the output raster. If all the input cell sizes are the same, all the options will yield the same results.
