Convert µS/cm to ppm (TDS) by multiplying conductivity by your meter’s factor, 0.5, 0.64 or 0.7, or convert ppm back to µS/cm; mS/cm and dS/m work too.
- All Unit Converters
- mg/l to ppt Converter
- g/mol To ppm Calculator
- ppm To mol/L Calculator
- Grams To mEq Calculator
µS/cm to ppm Formula
The following formula is used to estimate total dissolved solids in parts per million from electrical conductivity measured in microsiemens per centimeter.
Variables:
- ppm is the estimated total dissolved solids in parts per million
- EC is the electrical conductivity in microsiemens per centimeter (µS/cm)
- f is the selected conversion factor, typically between 0.5 and 0.7
To calculate ppm from µS/cm, multiply the conductivity reading by the appropriate conversion factor for the water type, calibration scale, or meter setting being used.
What is µS/cm to ppm Conversion?
µS/cm to ppm conversion is a practical method used to estimate total dissolved solids from an electrical conductivity reading. Because dissolved minerals and salts conduct electricity, conductivity can be used as an indirect indicator of how much material is dissolved in water. However, the relationship is not exact, since different ions conduct differently. For that reason, ppm is usually estimated with an empirical conversion factor rather than a fixed universal ratio.
Many conductivity and TDS meters let users choose a factor such as 0.5, 0.64, or 0.7. Factors depend on the instrument scale and dissolved substances; a water-type name alone does not determine the correct factor. Knowing which factor your instrument uses helps you compare readings more accurately. Use temperature-compensated EC (commonly referenced to 25 °C) when the scale requires it; the calculator does not apply temperature compensation. Meter ppm commonly denotes an estimated mg/L value for dilute water; exact mass-fraction ppm (mg/kg) also depends on density. See the Hanna Instruments meter manual.
How to Convert µS/cm to ppm?
The following steps outline how to convert a conductivity reading in µS/cm to an estimated ppm value.
- First, determine the conductivity reading in microsiemens per centimeter (µS/cm).
- Next, select the factor specified by your meter or applicable calibration data, using the same temperature reference.
- Then, multiply the conductivity reading by the factor using the formula ppm ≈ EC × f.
- Finally, compare the result with the calculator above to verify your answer.
µS/cm to ppm Conversion Table
The table below shows arithmetic estimates for 1000 µS/cm using illustrative factors. These are not universal factors for particular water types.
| Example factor | Selected factor | 1000 µS/cm in ppm |
|---|---|---|
| Factor 0.50 example | 0.50 | 500 ppm |
| Factor 0.55 example | 0.55 | 550 ppm |
| Factor 0.60 example | 0.60 | 600 ppm |
| Factor 0.64 example | 0.64 | 640 ppm |
| Factor 0.67 example | 0.67 | 670 ppm |
| Factor 0.70 example | 0.70 | 700 ppm |
| Factor 0.75 example | 0.75 | 750 ppm |
Different meters may report different ppm values for the same conductivity reading if they use different conversion factors. That is why it is important to understand whether your meter is using a 0.5 scale, a 0.64 scale, a 0.7 scale, or another setting.
Example Problem:
Use the following variables as an example problem to test your knowledge.
Conductivity (EC) = 1500 µS/cm
Conversion Factor (f) = 0.64
Estimated ppm = 1500 × 0.64 = 960 ppm
