CalMacroCalc
Electrolytes Calculator Scientific sodium, potassium & magnesium — EFSA/NIH/ACSM 2024

Weight in kilograms (kg).
All fluids consumed per day (water, drinks, intra-workout).
Affects magnesium needs.
+ Advanced Options
Duration of active training (for sweat estimation).
Adjusts sodium needs based on sweat loss.

Sodium (Na⁺)

0 mg

Essential for fluid balance & nerve function. ⓘ Base = Fluid Intake × 1000 mg (min 3000 mg)
Adjusted by sweat rate

→ ⚠️ <3000 mg may cause cramps or hyponatremia.

Potassium (K⁺)

0 mg

Critical for heart rhythm, muscle recovery, and hydration. ⓘ Base = Weight × 45 mg
+ (Sodium ÷ 1000) × 400 mg

Magnesium (Mg²⁺)

0 mg

Supports 300+ enzymes, muscle relaxation, and sleep. ⓘ Base = Weight × 5.5 mg
+ Bonus: Inactive=0 / Resistance=50 / Resistance+Cardio=100

→ ⚠️ Low Mg²⁺: twitching, insomnia. Best from food.

Sodium : Potassium Ratio

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Optimal for athletes: 1 : 1 → 1 : 1.5

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+ 💡 Practical Tips (Food & Hydration)
Disclaimer: Values align with EFSA (2023), NIH (2024), and ACSM (2023). For precision, consider sweat testing. Consult a physician before high-dose supplementation — especially with kidney, heart, or BP conditions.