Parts per million to microsiemens per centimeter
Type a value in ppm to get it in µS/cm instantly.
That's about the same as the drinking water guideline. That is ordinary tap water, within the usual guidelines.
Convert the other way: µS/cm to ppm
What it means
How pure is that water?
A TDS meter does not measure solids. It measures conductivity and multiplies, so anything dissolved that does not conduct — sugar, for instance — is invisible to it.
The math
How to convert ppm to µS/cm
A TDS meter multiplies conductivity by a fixed factor: ppm = µS/cm × scale, where the scale is 0.5 for NaCl, 0.64 for hydroponics and 0.7 for 442. The figures below use the scale selected above.
Example: 500 ppm = 1,000 µS/cm.
The table below uses NaCl scale (× 0.5).
Every unit
Your reading in every unit
Tables
ppm to µS/cm conversion table
| ppm | µS/cm |
|---|---|
| 10 ppm | 20 µS/cm |
| 50 ppm | 100 µS/cm |
| 100 ppm | 200 µS/cm |
| 250 ppm | 500 µS/cm |
| 500 ppm | 1,000 µS/cm |
| 800 ppm | 1,600 µS/cm |
| 1,000 ppm | 2,000 µS/cm |
| 1,500 ppm | 3,000 µS/cm |
| 3,000 ppm | 6,000 µS/cm |
| 10,000 ppm | 20,000 µS/cm |
| 35,000 ppm | 70,000 µS/cm |
µS/cm to ppm conversion table
| µS/cm | ppm |
|---|---|
| 10 µS/cm | 5 ppm |
| 50 µS/cm | 25 ppm |
| 100 µS/cm | 50 ppm |
| 250 µS/cm | 125 ppm |
| 500 µS/cm | 250 ppm |
| 800 µS/cm | 400 ppm |
| 1,000 µS/cm | 500 ppm |
| 1,500 µS/cm | 750 ppm |
| 3,000 µS/cm | 1,500 ppm |
| 10,000 µS/cm | 5,000 ppm |
| 35,000 µS/cm | 17,500 ppm |
Quick answers
Quick answers
- How many µS/cm is 1 ppm?
- 1 ppm is 2 µS/cm.
- How many µS/cm is 10 ppm?
- 10 ppm is 20 µS/cm.
- How many µS/cm is 500 ppm?
- 500 ppm is 1,000 µS/cm.
The units
About these units
Parts per million (ppm)
Total dissolved solids, as a TDS meter reports it.
Microsiemens per centimeter (µS/cm)
Conductivity, which is what the probe actually measures.
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