mg/dL To mEq/L Calculator: Convert mg/dL To mEq/L (+ Formula)

Both mg/dL and mEq/L are units of concentration (in water solutions). Converting mg/dL to mEq/L is a bit difficult; that’s why we created a calculator that converts mg/dL (milligrams per deciliter) to mEq/L (milliequivalents per liter).

On top of that, we also created two 0.01-500 mg/dL to mEq/L conversion charts for potassium (K+) and calcium (Ca2+) that can help you out.

Quick Example: How many mEq/L is 15 mg/dL of sodium chloride (NaCl)? In the calculator, we input 15 mg/dL, the molecular weight of NaCl (58.44 g/mol), and the +1 valence or charge of the main atom (Na1+). We see right away that 15 mg/dL NaCl is equal to 2.57 mEq/L.

Here is this online calculator, followed by mg/dL to mEq/L formula and 2 useful conversion charts:


Let’s solve an example to illustrate how this calculator works:

How many mEq/L is 30 mg/dL solution of magnesium chloride (MgCl2)? We insert ’30’ in the 1st mg/dL input field, look up the molecular weight – 95.21 g/mol for MgCl2) – and insert ‘95.21‘ in the 2nd input field, and, since magnesium forms 2+ valence ions, we slide the valence slider to ‘+2’, and get the result in this form (screenshot):

converting mg dl to meq l with an online calculator

We can see that 30 mg/dL of MgCl2 is equal to 6.30 mEq/L.

Now, let’s have a look at the math behind this conversion:

mg/dL To mEq/L Formula

Here are the units of concentration in the water solution we are dealing with:

  • mg/dL stands for milligrams per deciliter. 1 mg/dL simply means that 1 mg of a chemical substance is dissolved in 1 dL of water (or 100 ml of water).
  • mEq/L stands for milliequivalents per liter. 1 mEq/L is a concentration of 1 milliequivalent of chemical substance (reacts with 1 mmol of another substance) dissolved in 1 L of water.

Now, to convert mg/dL to mEq/L we use the following formula:

mEq/L = mg/dL × Valence (Charge) × 10 / MW

Here are the variables:

  • “Valence” or “Charge” is usually the ion charge of the main atom in the chemical substance (Ca2+ in CaCO3, for example, has a valence of +2).
  • MW is the Molecular Weight of the molecule. By the way, we include a table with molecular weights and valence for the most common molecules in the appendix below.
  • Factor 10 comes from converting dL to L (1 L = 10 dL).

Let’s solve another example to see how to use this formula:

How many mEq/L is in a 100 mg/dL solution of sodium hydroxide (NaOH)? We know we have a 100 mg/dL solution, the molecular weight of NaOH is 40.00 g/L, and we know that Na1+ has a valence of +1. Let’s insert all these numbers in the equation above like this:

mEq/L (30 mg/dL NaOH) = 30 mg/dL × (+1) × 10 / 40.00 g/mol25.00 mEq/L

We can see that 100 mg/dL NaOH solution is equal to 25 mEq/L solution. You can check this calculation with the calculator above.

Here are the two conversion charts (1st one for potassium, and the 2nd one for calcium):

Potassium mg/dL To mEq/L Conversion Chart

Potassium has an atomic weight of 39.1 g/mol and +1 valence. Here are the conversions:

Potassium mg/dL (K+): Potassium mEq/L:
0.01 mg/dL K+ 0.0026 mEq/L
0.1 mg/dL K+ 0.026 mEq/L
1 mg/dL K+ 0.26 mEq/L
2 mg/dL K+ 0.51 mEq/L
3 mg/dL K+ 0.77 mEq/L
4 mg/dL K+ 1.02 mEq/L
5 mg/dL K+ 1.28 mEq/L
10 mg/dL K+ 2.56 mEq/L
20 mg/dL K+ 5.12 mEq/L
30 mg/dL K+ 7.67 mEq/L
40 mg/dL K+ 10.23 mEq/L
50 mg/dL K+ 12.79 mEq/L
60 mg/dL K+ 15.35 mEq/L
70 mg/dL K+ 17.90 mEq/L
80 mg/dL K+ 20.46 mEq/L
90 mg/dL K+ 23.02 mEq/L
100 mg/dL K+ 25.58 mEq/L
150 mg/dL K+ 40.49 mEq/L
200 mg/dL K+ 53.99 mEq/L
250 mg/dL K+ 67.49 mEq/L
300 mg/dL K+ 80.98 mEq/L
350 mg/dL K+ 94.48 mEq/L
400 mg/dL K+ 107.98 mEq/L
450 mg/dL K+ 121.47 mEq/L
500 mg/dL K+ 134.97 mEq/L

From the chart, you can see that when we convert potassium mg/dL to mEq/L, the resulting mEq/L concentration is about 3-4 lower than the initial mg/dL concentration.

Calcium mg/dL To mEq/L Conversion Chart

Calcium has an atomic weight of 40.08 g/mol and +2 valence. Here are the conversions:

Calcium mg/dL (Ca2+): Calcium mEq/L:
0.01 mg/dL Ca2+ 0.005 mEq/L
0.1 mg/dL Ca2+ 0.05 mEq/L
1 mg/dL Ca2+ 0.50 mEq/L
2 mg/dL Ca2+ 1.00 mEq/L
3 mg/dL Ca2+ 1.50 mEq/L
4 mg/dL Ca2+ 2.00 mEq/L
5 mg/dL Ca2+ 2.50 mEq/L
10 mg/dL Ca2+ 4.99 mEq/L
20 mg/dL Ca2+ 9.98 mEq/L
30 mg/dL Ca2+ 14.97 mEq/L
40 mg/dL Ca2+ 19.96 mEq/L
50 mg/dL Ca2+ 24.95 mEq/L
60 mg/dL Ca2+ 29.94 mEq/L
70 mg/dL Ca2+ 34.93 mEq/L
80 mg/dL Ca2+ 39.92 mEq/L
90 mg/dL Ca2+ 44.91 mEq/L
100 mg/dL Ca2+ 49.90 mEq/L
150 mg/dL Ca2+ 74.85 mEq/L
200 mg/dL Ca2+ 99.80 mEq/L
250 mg/dL Ca2+ 124.75 mEq/L
300 mg/dL Ca2+ 149.70 mEq/L
350 mg/dL Ca2+ 174.65 mEq/L
400 mg/dL Ca2+ 199.60 mEq/L
450 mg/dL Ca2+ 224.55 mEq/L
500 mg/dL Ca2+ 249.50 mEq/L

With calcium, we see that the concentration in mEq/L is about half of the concentration in mg/dL.

We hope that the mg/dL to mEq/L online calculator, formula, and these 2 charts help you with this conversion. If you need a bit of help, you can always use the comment section below, describe the conversion you are trying to make, and we can help you out.

Appendix: Atomic Weight Table With Ion Valence

Main Atom: Atomic Weight: Valence (Charge):
K (Potassium) 39.1 g/mol 1
Na (Sodium) 23.0 g/mol 1
Li (Lithium) 6.94 g/mol 1
Ca (Calcium) 40.08 g/mol 2
Mg (Magnesium) 24.3 g/mol 2
Fe (Iron 3-valent): 55.85 g/mol 3
Cu (Copper 2-valent): 63.55 g/mol 2
Zn (zinc 2-valent): 65.38 g/mol 2
F (Fluoride): 19.0 g/mol 1
Cl (Chloride): 25.45 g/mol 1
Br (Bromide): 79.9 g/mol 1
O (Oxide): 16.0 g/mol 2
S (Sulfur): 32.07 g/mol 2
P (Phosphor): 30.97 g/mol 3
N (Nitrogen): 16.0 g/mol 3
C (Carbon): 12.0 g/mol 4

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