Convert Calcium Meq/L to Calcium ppm

Calcium Meq/L to Calcium ppm Conversion

Meq/L (milliequivalents per liter) is a unit that tells how many milliequivalents of calcium ions are present in one liter of water or soil solution.
ppm (parts per million) is a way to express the concentration of calcium in terms of weight, meaning how many milligrams of calcium are there in one liter of water (since 1 ppm = 1 mg/L).

Why convert?

Farmers often get water or soil test results showing calcium in Meq/L, but for practical use and comparison with fertilizer recommendations, ppm is easier to understand.

How to convert Calcium Meq/L to ppm?

Understand the atomic weight and charge of Calcium:

Atomic weight of Calcium (Ca) = 40 g/mol
Charge of Calcium ion (Ca²⁺) = 2 (because it has a +2 charge)

Formula to convert:

$ppm Ca=Meq/L\timesAtomic weight/Charge$

For calcium:

$ppm Ca=Meq/L\times40/2=Meq/L\times20$

Example:

If your water has 5 Meq/L of calcium,

$ppm Ca=5\times20=100 ppm$

This means there are 100 milligrams of calcium in every liter of water.

You can find more agriculture conversion calculators here.

Your Cart