Magnesium Dosage Calculator
Approximately 50% of Americans don't get enough magnesium. This calculator gives you a personalized dosage recommendation based on your body weight and health goal — not a one-size-fits-all number.
How This Calculator Works
Our calculator uses weight-based dosing from clinical research. The RDA for magnesium is 400-420mg/day for men and 310-320mg/day for women from all sources (food + supplements). Most people get 200-250mg from food, so the supplemental gap is 100-250mg.
Magnesium Forms Compared
| Form | Best For | Absorption | Side Effects |
|---|---|---|---|
| Glycinate | Sleep, anxiety, general | High | Minimal (gentle) |
| Citrate | Constipation, general | High | Loose stools at high doses |
| Threonate | Brain fog, cognitive | High (brain) | More expensive |
| Malate | Fatigue, fibromyalgia | Moderate-High | Minimal |
| Taurate | Heart health, blood pressure | Moderate | Minimal |
💊 Go Deeper on Magnesium
This calculator gives you the dose. Our full guide covers every form, timing, drug interactions, and which brands are worth buying.
FAQ
When should I take magnesium?
Glycinate: 30-60 min before bed (calming effect). Citrate: with meals. Threonate: morning or evening — timing matters less. Split doses (morning + evening) if taking over 200mg for better absorption.
Can I take too much?
From food: nearly impossible. From supplements: stay under 350mg/day (the tolerable upper limit). Higher doses cause diarrhea (especially oxide and citrate). People with kidney disease should consult a doctor.
How long before I feel the effects?
Sleep: 1-2 weeks. Anxiety: 2-4 weeks. Muscle cramps: a few days. Blood pressure: 8-12 weeks. Consistency matters more than dose.