S/m · mS/cm · µS/cm · Ω·m

Conductivity and Resistivity Converter

Convert conductivity and resistivity with live results, clear formulas and a graph. Explore optional temperature correction, estimated TDS and batch export.

Choose source and destination units; results update as you type. Conductivity and resistivity units can be selected in either direction. Negative values are not supported.

Try an example:

Converted value

All equivalent values

Electrical conductivity

S/m
S/cm
mS/cm
µS/cm
µS/m
dS/m
mho/m
mho/cm

Electrical resistivity

Ω·m
Ω·cm
kΩ·cm
MΩ·cm
mΩ·m

Formula and calculation

Conductivity and resistivity graph

The curve is ρ = 1/σ for positive scalar conductivity, at the same temperature. The dot marks your input. Both axes are logarithmic in log mode, so the reciprocal relationship becomes a straight line. Move over the graph to inspect values.

Temperature compensation estimate

This optional linear approximation uses the conductivity above: σref = σT / [1 + α(T − Tref)], with α expressed per °C. The coefficient is solution-specific; 2%/°C is only an editable example. Use a validated coefficient over a limited temperature range. This is not nonlinear or ultrapure-water compensation and does not change the main results.

EC and estimated TDS

Estimated result

TDS (mg/L) ≈ factor × EC (µS/cm). Factors 0.5 and 0.7 are common conventions, not universal constants. Composition changes the relationship. EC → TDS uses the main conductivity without the optional temperature correction; the reverse calculation is independent. Neither EC nor estimated TDS establishes drinking-water safety.

Batch conversion

Enter one value per line or separate values with semicolons, up to 100 values. A decimal point or comma is accepted; do not use thousands separators. The units above apply to every row.

S ≠ S/m · Ω ≠ Ω·m

S measures conductance; S/m measures conductivity. Ω measures resistance; Ω·m measures resistivity. Geometry is needed to relate conductance to conductivity. The old unit mho equals S. Unit conversion alone does not correct temperature.

Try an example

1 mS/cm = 1,000 µS/cm = 0.1 S/m = 1 dS/m
1 S/cm = 100 S/m
500 µS/cm = 0.05 S/m ↔ 20 Ω·m
1 MΩ·cm = 10,000 Ω·m ↔ 1 µS/cm

Temperature compensation estimate

This optional linear approximation uses the conductivity above: σref = σT / [1 + α(T − Tref)], with α expressed per °C. The coefficient is solution-specific; 2%/°C is only an editable example. Use a validated coefficient over a limited temperature range. This is not nonlinear or ultrapure-water compensation and does not change the main results.

Hanna Instruments

EC and estimated TDS

TDS (mg/L) ≈ factor × EC (µS/cm). Factors 0.5 and 0.7 are common conventions, not universal constants. Composition changes the relationship. EC → TDS uses the main conductivity without the optional temperature correction; the reverse calculation is independent. Neither EC nor estimated TDS establishes drinking-water safety.

Hanna Instruments

Conductivity and Resistivity Converter

S ≠ S/m · Ω ≠ Ω·m

S measures conductance; S/m measures conductivity. Ω measures resistance; Ω·m measures resistivity. Geometry is needed to relate conductance to conductivity. The old unit mho equals S. Unit conversion alone does not correct temperature.

Conductivity and resistivity graph

The curve is ρ = 1/σ for positive scalar conductivity, at the same temperature. The dot marks your input. Both axes are logarithmic in log mode, so the reciprocal relationship becomes a straight line. Move over the graph to inspect values.

Temperature compensation estimate

This optional linear approximation uses the conductivity above: σref = σT / [1 + α(T − Tref)], with α expressed per °C. The coefficient is solution-specific; 2%/°C is only an editable example. Use a validated coefficient over a limited temperature range. This is not nonlinear or ultrapure-water compensation and does not change the main results.

EC and estimated TDS

TDS (mg/L) ≈ factor × EC (µS/cm). Factors 0.5 and 0.7 are common conventions, not universal constants. Composition changes the relationship. EC → TDS uses the main conductivity without the optional temperature correction; the reverse calculation is independent. Neither EC nor estimated TDS establishes drinking-water safety.