Estimate total dissolved solids from conductivity and a conversion factor.
| TDS (mg/L) | – |
Use this calculator for a water test when the meter reads µS/cm and you want a TDS number for a report.
The calculation is TDS (mg/L) ≈ conductivity × factor. 0.65 is a common default; 0.5–0.7 is the usual band.
This is an estimate from conductivity, not a gravimetric TDS after evaporation.
Conductivity (µS/cm): Conductivity in µS/cm (same as µmho/cm) from the meter.
Factor k: TDS factor, typically 0.5 to 0.7. Use 0.65 if you were not told otherwise.
TDS (mg/L): Estimated total dissolved solids in mg/L.
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