Magnesium Comparison Calculator

Compare magnesium supplement forms by elemental content, absorption rate, and effective dose per tablet.

Magnesium Form

Tablet Size (mg)

Tab to move between fields

Elemental Mg

64 mg

Effective Dose

18 mg

Absorption Rate28%

Best For (1=gen,2=sleep,3=bulk,4=brain,5=heart)1

How to Use This Calculator

Enter your target elemental magnesium dose per day in mg.
Select the magnesium form: oxide, citrate, glycinate, malate, or threonate.
Input the number of capsules or tablets per dose in the product you are evaluating.
Review the Elemental Magnesium per Serving, Bioavailability Score, and Cost per 100 mg Elemental.
Use the Form Comparison table to identify the highest-bioavailability form within your budget.

How the result changes with Tablet Size (mg)

Magnesium Form: 1 = Citrate (general), 2 = Glycinate (sleep), 3 = Oxide (bulk), 4 = Threonate (brain), 5 = Taurate (heart)
Tablet Size (mg): Total milligrams of the magnesium compound per tablet (not elemental Mg)

Identify Input Parameters
Magnesium Form = 1, Tablet Size (mg) = 400 = 2 input(s) provided
Calculate Elemental Mg
Elemental Mg
64 = 64
Calculate Effective Dose
Effective Dose
18 = 18
Calculate Absorption Rate
Absorption Rate
28 = 28

Engine last updated July 26, 2026. Checked against 3 independently-derived tests — how we verify calculators.

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