Homemade Electrolyte Mix Calculator
Mix your own oral rehydration drink — how much salt, sugar and potassium to add per litre of water to hit a target sodium concentration.
How it works
Salt (g) = volume × sodium mg/L ÷ 393 · Sugar (g) ≈ 25 × volume · KCl (g) = volume × 300 ÷ 524
A basic oral rehydration solution is water, a little sodium, some sugar to drive sodium-glucose co-transport in the gut, and optionally potassium. Table salt is about 39.3% sodium by weight, so 1 g of salt supplies roughly 393 mg of sodium; divide your total sodium goal by 393 to get the grams of salt. A modest amount of sugar improves both taste and water absorption, and potassium is easily added using a lite (part-potassium) salt.
Worked example
For 1 L at a 500 mg/L sodium target, you need 500 ÷ 393 = 1.27 g of table salt (about a quarter teaspoon), plus roughly 25 g of sugar. Adding potassium at 300 mg/L means 300 ÷ 524 = 0.57 g of potassium chloride from lite salt.
Frequently asked questions
How much sodium should the drink have?
Sports drinks run about 230–500 mg/L, while a medical oral rehydration solution for illness is stronger, near 1,000 mg/L. Match the concentration to your need — sweat replacement versus recovering from fluid loss.
Why add sugar at all?
Glucose helps the gut absorb sodium and water together through co-transport, which is the principle behind oral rehydration. It also makes the drink palatable enough to keep sipping.
Is homemade as good as a commercial mix?
For everyday hydration it can be, but for treating significant dehydration from illness a standardised oral rehydration formula is safer — precise ratios matter more there.
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Educational estimate, not medical advice. Talk to a doctor, pharmacist or registered dietitian before starting or changing any supplement, especially if you are pregnant, nursing, on medication or managing a health condition.