About the DIY Electrolyte Drink Calculator
This homemade electrolyte drink calculator tells you exactly how much table salt, potassium chloride (salt substitute) and sugar to dissolve in a bottle of water to reach a target sodium, potassium and carbohydrate concentration. Choose a sports-drink style mix, a low-sugar electrolyte for heavy sweaters, an oral-rehydration-style recipe based on WHO concentrations, or set your own targets.
It is useful for endurance athletes matching their sweat losses, people who want a cheaper or less sugary alternative to bottled sports drinks, and anyone who wants to know what is really in their mix. Results are given in grams for a kitchen scale, with approximate teaspoons for salt and sugar, plus the millimoles per litre, estimated osmolarity and calories.
Sodium comes only from the salt and potassium only from potassium chloride (sold as “NoSalt”, “Nu-Salt” and similar). Weigh potassium chloride carefully — large amounts are dangerous. For dehydration from diarrhoea or vomiting, especially in children, older adults or people with kidney or heart disease, use a commercial oral rehydration solution and seek medical advice rather than a home mix.
With the default inputs, the table salt to add is 1.27 g. Change any value above to recalculate instantly.
How to use the diy electrolyte drink calculator
- 1Pick a drink type, or choose Custom and enter your own sodium, potassium and carbohydrate targets.
- 2Enter the batch size in litres or fluid ounces.
- 3Choose table sugar or dextrose as the carbohydrate.
- 4Weigh out the salt, potassium chloride and sugar shown and dissolve them in the water.
- 5Check the osmolarity note and adjust if the drink is too concentrated.
Formula and method
Table salt (sodium chloride) is 39.34% sodium by mass, so each gram provides 393.4 mg of sodium; potassium chloride is 52.45% potassium, so each gram provides 524.5 mg of potassium. Multiplying the target concentration by the batch volume and dividing by these figures gives grams to weigh. Teaspoons use 6 g per level teaspoon of fine salt and 4.2 g for granulated sugar.
Concentrations in mmol/L divide milligrams by atomic mass (sodium 22.99, potassium 39.10). Osmolarity is estimated as twice the sodium chloride and potassium chloride millimoles (each splits into two ions) plus the sugar millimoles (sucrose 342.3 g/mol, glucose 180.2 g/mol). The ORS preset uses the WHO reduced-osmolarity targets of 75 mmol sodium, 20 mmol potassium and 13.5 g glucose (75 mmol) per litre — or 25.7 g of sucrose, the same 75 mmol, if you choose table sugar; because WHO ORS also contains citrate, this all-chloride version is an approximation.
- V
- Batch volume in litres
- Na, K
- Target sodium and potassium in mg per litre
- C
- Target carbohydrate in g per litre (10 g/L = 1%)
Worked examples
1 L sports-drink style mix
For 500 mg sodium, 150 mg potassium and 60 g sugar per litre you need 500 ÷ 393.4 = 1.27 g salt, 150 ÷ 524.5 = 0.29 g potassium chloride and 60 g sugar (about 14 teaspoons). That is 21.7 mmol/L sodium, roughly 226 mOsm/L and 240 kcal.
ORS-style litre with dextrose
75 mmol of sodium is 1,724 mg, which needs 4.38 g of salt; 20 mmol of potassium (782 mg) needs 1.49 g of potassium chloride, plus 13.5 g of dextrose. With all sodium as chloride the estimated osmolarity is about 265 mOsm/L.
32 oz low-sugar custom mix
32 fl oz is 0.946 L. Hitting 1,000 mg/L sodium takes 0.946 × 1,000 ÷ 393.4 = 2.41 g of salt (about 0.4 teaspoon) and 300 mg/L potassium takes 0.54 g of potassium chloride, with zero calories.
Frequently asked questions
How much salt should I put in an electrolyte drink?+
Sports drinks typically contain about 450–700 mg of sodium per litre, which is roughly 1.1–1.8 g (about ¼ teaspoon) of table salt. Heavy or salty sweaters often use 800–1,500 mg per litre, while ORS contains about 1,700 mg.
What can I use for potassium in a homemade electrolyte drink?+
Potassium chloride salt substitutes such as NoSalt or Nu-Salt are the simplest source. Orange juice, coconut water and bananas add some potassium too, but are harder to dose precisely. Never take more potassium chloride than a recipe calls for.
Do I need sugar in an electrolyte drink?+
Not for short or easy workouts. Glucose helps the gut absorb sodium and water, which matters in oral rehydration, and carbohydrate (around 30–60 g per hour) fuels efforts longer than about 60–90 minutes.
Is a homemade drink as good as oral rehydration salts?+
For athletes it works well, but for treating diarrhoea or vomiting, pre-packaged WHO-formula ORS is safer because the proportions are exact and it includes citrate. Seek medical advice for dehydration in babies, children and older adults.
What is osmolarity and why does it matter?+
Osmolarity is the concentration of dissolved particles. Drinks below or near blood’s ~290 mOsm/L (hypotonic or isotonic) empty from the stomach and absorb quickly; very sugary, concentrated drinks are hypertonic and absorb more slowly.
This tool gives general estimates and is not medical advice. Talk to a doctor or qualified professional about your health, diet or training.