This document specifies two test methods for the determination of water content of raw rubber and compounded rubber using a coulometric Karl Fischer titration method. — Method A is a method using an evaporator of heating tube type oven. — Method B is a method using an evaporator of vial type oven. It applies to the water content range between 0,01 % and 1 %. As this is a very sensitive method, contact of sample with any moisture, even from the surrounding environment, must be eliminated as much as possible. In case of dispute, method B is the preferred method.