LSI (Langelier Saturation Index) calculator

PRO

Langelier Saturation Index — target between -0.3 and +0.3.

Inputs

Result

LSI
-0.19
Balanced

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The formula

LSI = pH + TF + CF + AF − TDS constant.

Worked example

pH 7.5, 78°F, CH 250, TA 100, TDS 1000 → LSI ≈ 0.0 (balanced).

Frequently asked

Target range?

-0.3 to +0.3. Below = corrosive; above = scale forming.