To convert a TDS value from mg/L to ppm:
Use the formula to go from a concentration in mg/L to ppm:
[ppm] = [mg/L] × 1000 / density [kg/m³]
Since TDS is a quality parameter commonly associated with water, we'll see that the conversion becomes fairly easy assuming water density as 1000 kg/m³.
By substituting this value of density in the formula from step 1, we get:
[ppm] = [mg/L]
This means that for water, the TDS concentration value in mg/L is precisely the same as that of ppm.
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