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mg/L to mEq/L Converter
↔ Convert mEq/L to mg/L instead

Common Conversions

mg/L mEq/L
1 v/AW
5 5v/AW
10 10v/AW
20 20v/AW
50 50v/AW
100 100v/AW
200 200v/AW
500 500v/AW
1000 1000v/AW
2000 2000v/AW
5000 5000v/AW
10000 10000v/AW

Why this conversion matters in chemistry

Consider pharmacy compounding. A 0.9% w/v normal saline IV bag holds 3219 mg/L of Na, equivalently 140 mEq/L on the bedside electrolyte order. The conversion uses mEq/L = (mg/L × valence) / atomic weight; for Na (MW 22.99, valence 1) the factor is 1/23. The mass-based mg/L form is what compounding-pharmacy worksheets carry; the charge-based mEq/L is what bedside clinical-chemistry reports use. It comes up when bulk-formulation specs need to land in the per-charge form clinical electrolyte management runs in.

Formula

mEq/L = (mg/L × valence) ÷ atomic weight

Worked Examples

23 mg/L Na⁺ (AW 23, v=1) = 1 mEq/L

1 mEq of sodium — the conversion anchor for the most common clinical cation.

40 mg/L Ca²⁺ (AW 40, v=2) = 2 mEq/L

2 mEq of calcium — divalent, so the mEq scale is double the mass-equivalent.

39.1 mg/L K⁺ (AW 39.1, v=1) = 1 mEq/L

1 mEq of potassium — the second monovalent clinical electrolyte.

35.5 mg/L Cl⁻ (AW 35.5, v=1) = 1 mEq/L

1 mEq of chloride — the principal monovalent anion in extracellular fluid.

Frequently Asked Questions

How do I convert mg/L to mEq/L?
mEq/L = (mg/L × valence) ÷ atomic weight. So 23 mg/L of Na⁺ becomes (23 × 1) / 23 = 1 mEq/L. Both the atomic weight and valence are needed.
Why are two factors needed?
Atomic weight converts mass to moles; valence converts moles to equivalents. The two-step chain is what carries the conversion from a mass-based mg/L into the per-charge mEq/L form clinical work uses.
Where is this conversion used?
Water-treatment hardness calculations, ion-exchange capacity work, clinical-laboratory quality control, and any cross-system reconciliation between mass-based reagent specs and charge-based clinical electrolyte data.