Conductivity Unit Converter

Conductivity is reported in µS/cm on a meter, mS/cm on a datasheet and S/m in a standard method, and the zeros move fast enough to cause real errors. This converter switches exactly between µS/cm, mS/cm, S/m and S/cm using the reference values laboratories quote.

Convert conductivity unit units

Value

From

Why conductivity units collide

Conductivity spans six orders of magnitude across water types — from ultrapure water near 0.055 µS/cm to concentrated process streams above 1 S/cm. To keep numbers readable, the field uses three unit families (µS, mS, S) across two length bases (per cm and per m), which is exactly where a misplaced factor of ten slips in.

The relations are exact: 1 S/m = 10 mS/cm = 10 000 µS/cm, and 1 S/cm = 100 S/m. This converter applies them directly so the value you read matches the unit you selected.

Which unit to report

µS/cm is the field and laboratory standard for water quality. mS/cm appears on sensor and transmitter ranges. S/m is the SI unit and the one standards methods often state. Match the unit your limit or method uses, then convert for comparison.

Complete conversion reference

Convert 1 unit to	S/m	mS/m	µS/cm	mS/cm	S/cm
1 S/m	1	1000	10000	10	0.01
1 mS/m	0.001	1	10	0.01	1e-05
1 µS/cm	0.0001	0.1	1	0.001	1e-06
1 mS/cm	0.1	100	1000	1	0.001
1 S/cm	100	100000	1e+06	1000	1

Instruments for this measurement

CON100

3-in-1 pen tester: conductivity, TDS, salinity

Pocket · field inspection

CON200

Handheld conductivity / TDS / salinity tester

To 400 mS/cm · IP65

CON600

Benchtop conductivity / TDS / salinity meter

0.001 µS/cm resolution

CON3000C

98×98 mm panel conductivity transmitter

K=0.01–30 · TDS track

CON6000C

144×144 mm panel conductivity monitor

Wide cell-constant range

Models shown are representative families, not a complete catalogue. Send us your application, water analysis and installation constraints and we will match instruments to it.

Frequently asked

How many µS/cm in 1 mS/cm?

Exactly 1000 µS/cm. And 1 S/m = 10 mS/cm = 10 000 µS/cm. The converter keeps all four units so you can move between them without a misplaced zero.

What is a typical drinking-water conductivity?

Treated drinking water is often 50–800 µS/cm depending on mineral content; ultrapure water is near 0.055 µS/cm. Values climb into mS/cm for brackish and industrial streams.

Is conductivity the same as TDS?

No. Conductivity is a measured electrical property; TDS is a calculated mass estimate derived from it via a conversion factor (typically 0.5–0.7). For the factor and its limits, see the conductivity-to-TDS calculator.

Why does my meter read S/m sometimes?

S/m is the SI unit and what some standards state; field meters usually display µS/cm or mS/cm. They are the same quantity at different scale, so convert rather than treat them as different measurements.

This page performs exact unit arithmetic with no physical assumption beyond the stated reference (for example mH₂O assumes water near 4 °C, and pH follows its logarithmic definition). It is a working aid, not a substitute for the measurement method named in your permit.