TDS in Drinking Water: What Is Total Dissolved Solids & Safe Levels
Total dissolved minerals in water
Optimal Min in Water
50
Optimal Max in Water
300
Unit
ppm
Symbol
TDS
Who Limit
600
None
5 min read
Overview of Total Dissolved Solids (TDS) in Drinking Water
What it is: TDS measures the combined concentration of all inorganic and organic substances dissolved in water—including minerals, salts, metals, and trace elements. Expressed in parts per million (ppm) or mg/L.
Why it matters: TDS directly affects water taste, purity, and overall quality. It's the most reliable single indicator of how "pure" or "mineral-rich" your water is, making it the first metric experts check.
Natural sources: Minerals leach naturally from rocks, soil, and sediment. Additional sources include agricultural runoff, urban discharge, sewage, and pipe corrosion in aging infrastructure.
Optimal range (50–300 ppm): Water in this range tastes clean and refreshing while providing beneficial minerals. Most premium bottled waters and natural springs fall within this sweet spot.
Too high (>500 ppm): Water may taste salty, metallic, or bitter. Can indicate contamination, excessive hardness, or industrial pollution. WHO recommends staying below 600 ppm.
Too low (<50 ppm): Flat, empty taste lacking character. May be deficient in beneficial minerals. Commonly found in heavily filtered, distilled, or reverse osmosis water without remineralization.
