DIY Sports Drink Calculator

Work out exactly how much sugar and salt to stir into water for a homemade sports drink that matches commercial carbohydrate and sodium levels.

Quick Facts

Method
Sugar = volume × carb %; salt = sodium ÷ 393 mg/g
Table salt (NaCl) is 39.3% sodium by mass; a 6% carb mix is isotonic.

Your Recipe

Calculated
Sugar to add
-
Granulated sugar (sucrose)
Sugar in teaspoons
-
At ~4.2 g per level tsp
Salt to add
-
Table salt (NaCl)
Salt in teaspoons
-
At ~6 g per level tsp

Ready

Enter your batch size and targets, then calculate.

About the DIY sports drink calculator

A sports drink does two jobs at once: it delivers carbohydrate to fuel working muscles and it replaces the sodium you lose in sweat. This calculator turns those two goals into a simple recipe. You tell it how much drink you want to make, how strong you want the carbohydrate, and how much sodium to include, and it returns the grams and teaspoons of ordinary sugar and table salt to stir into plain water. Everything is built from real food chemistry rather than a brand's secret formula, so you can reproduce or tweak the mix at a fraction of the cost of a bottled drink.

The formula it uses

Two independent calculations run under the hood:

  • Sugar (carbohydrate). Carbohydrate concentration is given as a percentage weight-in-volume (% w/v), which means grams per 100 mL. So sugar (g) = (carb % ÷ 100) × volume in mL. A 6% drink therefore needs 60 g of sugar per litre.
  • Salt (sodium). Table salt is sodium chloride, NaCl. Sodium's share of that molecule by mass is 22.99 ÷ 58.44 = 0.393, so 1 gram of salt supplies 393 mg of sodium. To reach a sodium target, salt (g) = sodium (mg) ÷ 393. A 500 mg/L drink needs about 1.27 g of salt per litre — close to a quarter teaspoon.

The teaspoon figures come from standard kitchen densities: roughly 4.2 g of granulated sugar and 6 g of fine table salt per level teaspoon.

Sensible reference points

  • Carbohydrate 6% (isotonic): the classic sports-drink strength and the default here. Drinks in the 4–8% range empty from the stomach at about the same rate as water while still delivering fuel.
  • Sodium ~500 mg/L: matches mainstream commercial sports drinks (Gatorade and Powerade sit near 450–500 mg per litre). Heavy or salty sweaters, or long events in heat, may want 700–1000 mg/L.
  • Hypotonic (<4% carbs): lighter, absorbs quickly, good for short sessions or when you mainly need fluids.
  • Hypertonic (>8% carbs): more fuel per sip, like undiluted fruit juice or cola, but it draws water into the gut and can slow hydration.

A quick worked example

For a 500 mL bottle at 6% carbs and 500 mg/L sodium: sugar = 0.06 × 500 = 30 g (about 7 level teaspoons); salt = (500 × 0.5) ÷ 393 = 0.64 g (about one-eighth of a teaspoon). Add a squeeze of lemon or a splash of juice for flavour and you have a homemade equivalent of a shop-bought bottle.

Frequently Asked Questions

How much sugar and salt go in a homemade sports drink?
For a standard 6% isotonic drink, use 60 g of sugar per litre (30 g in a 500 mL bottle). For sodium, aim for about 500 mg per litre, which is roughly 1.3 g of table salt — a scant quarter teaspoon per litre. Dissolve both fully and add flavouring such as lemon juice to taste.
Why does the calculator ask for sodium instead of grams of salt?
Hydration guidance and product labels are written in milligrams of sodium, not grams of salt, so a sodium target lets you compare directly with your usual drink. The tool converts for you: because table salt is 39.3% sodium by mass, it divides your sodium goal by 393 to find the grams of salt to add.
Can I use honey, maple syrup, or fruit juice instead of sugar?
Yes. They mainly supply glucose and fructose just like table sugar, so they fuel the same way. The gram figures assume dry granulated sugar; liquid sweeteners are only about 75–80% carbohydrate by weight (the rest is water), so use a little more to hit the same carb concentration. Fruit juice already contains carbohydrate — dilute it with water to land in the 4–8% range.
Do I really need salt if I'm only exercising for 30–60 minutes?
For short, cool sessions plain water is usually enough and the sodium is optional. Sodium matters most for efforts over about an hour, in the heat, or if you sweat heavily or leave salty residue on your skin, where it helps you retain fluid and stave off cramps and hyponatraemia. When in doubt, a small amount (the ~500 mg/L default) is a safe, palatable level.

Related calculators