This calculator allows you to convert from Millimeter water (4°C) to Inch water (4°C) and in a reverse direction. To convert from Millimeter water (4°C) to Inch water (4°C), enter the amount of Millimeter water (4°C) into the first input and to convert from Inch water (4°C) to Millimeter water (4°C), enter the amount of Inch water (4°C) into the second input.