Salinity/TDS Converter

Salinity & TDS Converter

Use this TDS to salinity calculator to convert PSU to ppm, mg/L, and more. This free salinity and TDS converter gives accurate conversions between Practical Salinity Units (PSU), grams per kilogram (g/kg), milligrams per liter (mg/L), parts per million (ppm), and conductivity (μS/cm). Use it for oceanography, aquarium water, drinking water TDS, and environmental monitoring—results update instantly. No sign-up required. For mass fraction and ppm try our Concentration Converter, for conductivity units see the Electric Conductivity Converter, or use our Molarity Converter for mol/L and g/L.

Supported Unit Categories:

• Practical Salinity Units (PSU): Standard oceanographic salinity measurement
• Mass-based Units: Grams per kilogram (g/kg), parts per thousand (ppt)
• Concentration Units: Milligrams per liter (mg/L), parts per million (ppm)
• Conductivity Units: Siemens per meter (S/m), microsiemens per centimeter (μS/cm)

Salinity Measurement Systems:

• PSU (Practical Salinity Units): Based on electrical conductivity, used in oceanography
• g/kg (Grams per Kilogram): Mass ratio of dissolved salts to seawater
• mg/L (Milligrams per Liter): Mass concentration of dissolved solids
• ppt (Parts per Thousand): Traditional salinity measurement (‰)

Common Conversions:

• 35 PSU ≈ 35 g/kg ≈ 35,000 mg/L (typical ocean salinity)
• 0 PSU = 0 g/kg = 0 mg/L (freshwater)
• 1 PSU ≈ 1 g/kg ≈ 1,000 mg/L
• 1 g/kg = 1,000 mg/L (at 4°C, density ≈ 1 g/cm³)

How to Use:

1. Enter the salinity or TDS value you want to convert
2. Select the source unit from the "From" dropdown
3. Select the target unit from the "To" dropdown
4. View the converted result instantly
5. Use the swap button to quickly reverse the conversion

Applications:

This salinity and TDS converter is used by oceanographers, marine biologists, environmental scientists, water quality professionals, and aquarists for seawater salinity, aquarium TDS, drinking water quality, aquaculture, and research. Convert PSU to mg/L, ppm to salinity, or conductivity to salinity in one place.