Hydration & nutrition

Electrolyte Intake Calculator

Add foods, drinks, and supplements to see your daily sodium, potassium, magnesium, and calcium against personalised targets.

About Electrolyte Intake Calculator

The Electrolyte Intake Calculator helps you balance the four most important dietary electrolytes — sodium, potassium, magnesium, and calcium — against personalised daily targets. Targets adjust for sex, age, activity level, and estimated sweat loss. Add foods, drinks, and supplements to see exactly where you stand and which electrolyte you need more of.

Best uses

  • •Plan hydration and electrolyte replacement around endurance training, hot weather, or sauna sessions.
  • •Audit a typical day's eating to spot under-consumed minerals (most often potassium and magnesium).
  • •Choose between sports drinks, electrolyte tablets, and whole foods based on actual mg per serving.
  • •Manage low-sodium diets without falling short of essential minerals.

How to Use Electrolyte Intake Calculator

  1. Set your sex, age, activity level, and estimated daily sweat loss to personalise the targets.
  2. Use the quick-add presets for common foods, or add custom rows for your own meals.
  3. Adjust the servings field for portion size — half-serving values are allowed (e.g. 0.5).
  4. Watch the totals panel — green is on target, amber means you have room to top up, rose means you're over.
  5. Use the reference panel below to find specific foods rich in the electrolyte you're short on.

Foods rich in each electrolyte

Sodium-rich

Sports drinks, electrolyte tablets, pickles, olives, cheese, table salt, broth, soy sauce

Potassium-rich

Bananas, sweet potato, avocado, coconut water, beans, salmon, spinach, oranges

Magnesium-rich

Pumpkin seeds, almonds, dark chocolate, spinach, black beans, brown rice, edamame

Calcium-rich

Milk, yogurt, cheese, sardines with bones, fortified plant milk, kale, tofu, almonds

Electrolyte Intake Calculator FAQ

Everything you need to know about electrolyte balance, daily targets, and how to plan around training, illness, and hot weather.

Frequently Asked Questions

What are electrolytes and why do they matter?

Electrolytes are minerals that carry an electrical charge in your body fluids — mainly sodium, potassium, magnesium, calcium, and chloride. They control hydration, nerve signalling, muscle contraction, and acid-base balance. Imbalance can cause cramps, fatigue, dizziness, or in extreme cases dangerous heart and brain symptoms.

How are the daily targets calculated?

Defaults follow common adult guidelines from the Institute of Medicine and EFSA. Sodium starts at 1,500 mg (Adequate Intake) and rises with activity to reflect higher sweat loss. Potassium uses 3,400 mg (men) or 2,600 mg (women). Magnesium and calcium use age- and sex-adjusted recommendations. Sweat losses are added on top of base targets.

How much sodium and potassium do I lose in sweat?

On average, sweat contains about 900 mg of sodium and 200 mg of potassium per litre — though this varies widely between people. Endurance athletes can lose 1–2 litres per hour in heat, so replacement matters. The sweat field uses these averages.

Where do I find electrolyte values for foods?

Most packaged foods list sodium, potassium, and calcium on the nutrition label. For whole foods, USDA FoodData Central (fdc.nal.usda.gov) is a free, comprehensive reference. The presets in this calculator use typical USDA values per serving.

Can I drink too much water?

Yes. Drinking large volumes of plain water without enough sodium can cause hyponatremia (low blood sodium), which is dangerous. This is most common in endurance athletes, hot-environment workers, and during illness. Match high water intake with sodium from food, electrolyte drinks, or tablets.

Is this medical advice?

No. This is an educational planning tool. If you have heart, kidney, or blood pressure conditions, take medication that affects electrolytes, are pregnant, or train at extreme volumes, follow targets from your clinician or sports dietitian.

Pro Tips

  • • Most people get plenty of sodium from packaged foods — focus on potassium, magnesium, and calcium, which are commonly under-consumed.
  • • Pair high-water-loss days (long workouts, hot weather, sauna) with extra sodium and potassium, not just plain water.
  • • A banana, a handful of almonds, and a glass of milk together cover roughly 25% of daily potassium, magnesium, and calcium.
  • • Electrolyte tablets are an easy way to top up sodium without extra calories — read the label, brands vary widely.