A TDS meter measures the total number of dissolved solids in drinking water in parts per million (ppm). The meter calculates the TDS content in the water. The higher the value, the more solids are dissolved in the water.

The ZeroWater TDS meter is included in every ZeroWater water jug and filter system and can be ordered separately here (in case you want one extra or first want to measure your TDS before buying a jug)