The table below shows conversions between water conductivity and resistivity. It also converts resistivity to conductivity, and to parts per million or milligrams per liter (ppm, mg/L).

Water Quality Conductivity Conversion Table

mg/L

Sodium

Chloride

Total Dissolved

Solids as

mg/L CaCO3

Specific

Conductance

(Microsiemens/cm)

Specific

Resistance

Megaohm Ω

Grains

per Gallon

Sodium Chloride

0.05

0.043

0.105

9.5238

0.0029

0.1

0.085

0.212

4.71698

0.0060

0.2

0.170

0.424

3.55849

0.012

0.3

0.255

0.637

1.56985

0.018

0.4

0.340

0.848

1.17924

0.023

0.5

0.425

1.06

0.943396

0.029

0.6

0.510

1.273

0.785545

0.035

0.7

0.595

1.985

0.6734

0.041

0.8

0.680

1.696

0.589622

0.047

0.9

0.765

1.908

0.524109

0.053

1

0.85

2.12

0.471698

0.06

2

1.70

4.24

0.235849

0.12

3

2.55

6.37

0.156985

0.18

4

3.40

8.48

0.117924

0.23

5

4.25

10.6

0.094339

0.29

6

5.10

12.73

0.078554

0.35

7

5.95

14.85

0.06734

0.41

8

6.80

16.96

0.058962

0.47

9

7.65

19.08

0.05241

0.53

10

8.5

21.2

0.047169

0.58

20

17.0

42.4

0.023584

1.17

30

25.5

63.7

0.015698

1.75

40

34.0

84.8

0.011792

2.34

50

42.5

106.0

0.009433

2.92

60

51.0

127.3

0.007855

3.51

70

59.5

148.5

0.006734

4.09

80

68.0

169.6

0.005896

4.68

90

76.5

190.8

0.005241

100

85

212

0.004716

5.85

200

170

410

0.002439

11.70

300

255

610

0.001639

17.5

400

340

812

0.001231

23.4

500

425

1,008

0.000992

29.2

600

510

1,206

0.000829

35.1

700

595

1,410

0.000709

40.9

800

680

1,605

0.000623

46.8

900

765

1,806

0.000553

52.6

1,000

850

2,000

0.0005

58.5

2,000

1700

3,830

0.000261

117

3,000

2550

5,760

0.000176

175

4,000

3400

7,500

0.000133

234

5,000

4250

9,240

0.000108

292

6,000

5100

10,950

0.000091

351

7,000

5950

12,650

0.000079

409

8,000

6800

14,340

0.000069

468

9,000

7650

16,000

0.000062

526

10,000

8500

17,600

0.000056

585

Additional Resources