DIY Sports Drink Calculator (sugar and salt for a homemade electrolyte drink)

Understanding the DIY sports drink calculator — concept and principle

This calculator works out how much sugar and table salt to dissolve in water to make your own sports drink for long exercise, with a chosen carbohydrate strength and sodium content.

1 L sports drink recipe: with the default inputs the result is 240 kcal (energy · 26.1 mmol/L sodium).

How it is calculated

Sugar (g) = carbohydrate % × 10 × litres

Table salt (g) = sodium (mg/L) × litres ÷ 0.3934 ÷ 1,000

Energy (kcal) = sugar (g) × 4

Sodium (mmol/L) = sodium (mg/L) ÷ 22.99

A 1% solution holds 10 g of carbohydrate per litre, so 6% means 60 g per litre.
Table salt is sodium chloride. Sodium makes up 22.99 ÷ 58.44 = 39.34% of its mass, so you divide the sodium you want by 0.3934 to get the salt.
The calculator also checks whether your recipe sits inside the ranges of 4–8% carbohydrate and 500–700 mg of sodium per litre.

The principle

During exercise lasting more than about an hour, muscles use up stored carbohydrate and sweat carries away water and sodium. The American College of Sports Medicine recommended drinks with 4–8% carbohydrate and 0.5–0.7 g of sodium per litre. At usual drinking rates this supplies 30–60 g of carbohydrate an hour, and the sodium helps the body hold on to the fluid and keeps the drink palatable.

Worked example

Default inputs: 1 L of drink, 6% carbohydrate, 600 mg of sodium per litre.

Sugar = 6 × 10 × 1 = 60 g.
Salt = 600 × 1 ÷ 0.3934 ÷ 1,000 = 1.525 g, shown as 1.53 g.
Energy = 60 × 4 = 240 kcal.
Sodium = 600 ÷ 22.99 = 26.1 mmol/L.
Both values sit inside 4–8% and 500–700 mg/L, so the check reads Yes.

Each point is the calculator re-run with only “Volume to make (L)” changed; the gold point is the default example. Change the inputs above and this chart follows your numbers.

Volume to make (L)	Sugar (g)
0.25	15
0.5	30
0.75	45
1	60
1.25	75
1.5	90
2	120

How to read the result

A result of "Yes" means your recipe matches the recommended ranges for long exercise. Below 4% the drink gives little energy; above 8% it may sit heavily in the stomach. If you sweat heavily or exercise in heat, staying near the upper sodium value is reasonable, but more is not automatically better. For sessions under an hour, water alone is usually enough.

Common mistakes

Measuring salt with a spoon. A quarter teaspoon weighs about 1.5 g but varies with the grain, so use a kitchen scale.
Forgetting the sugar already in juice or honey. Count it from the label and include it in the percentage.
Using this drink to treat diarrhoea or vomiting. Oral rehydration solution has a different recipe.

Keep in mind: This is general information, not a diagnosis or medical advice. People with high blood pressure, kidney or heart disease, or on a salt-restricted diet should ask a doctor before adding salt to drinks.

Frequently asked questions

Can I use honey or juice instead of sugar?

Yes. Add up the grams of sugars from the label and divide by the volume in mL, then multiply by 100 to get the percentage.

How much should I drink per hour?

It depends on sweat rate, heat and body size. Many athletes drink small amounts regularly rather than a fixed volume; weighing yourself before and after training shows how much you lost.

Is a homemade drink as good as a commercial one?

For carbohydrate and sodium it can match the same ranges. Commercial drinks may add potassium, flavour and other ingredients.

Sources: American College of Sports Medicine position stand, "Exercise and Fluid Replacement", Med Sci Sports Exerc 1996;28(1):i–vii · IUPAC standard atomic weights (Na 22.99, Cl 35.45)

Checked 9 Nov 2026. American College of Sports Medicine position stand, “Exercise and Fluid Replacement”, Med Sci Sports Exerc 1996;28(1):i–vii (Convertino VA et al.): 4–8% carbohydrate, 0.5–0.7 g/L sodium, 30–60 g carbohydrate per hour for exercise over 1 h (as summarised in the ACSM statement summary posted by the Oregon School Activities Association and the SPORTIF record); atomic masses Na 22.99 and Cl 35.45 (IUPAC).

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