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):
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:
Table of Contents
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/mol = 25.00 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 |