SportingDrinks

Hydration calculator for athletes

Enter your weight, session and conditions. You get fluid, sodium and carb targets for each hour, and the drinks from our label database that fit them best.

Your session

Session length

Intensity

Easy is a pace you could chat at. Hard is race effort.

How much do you sweat?
How salty is your sweat?

White salt marks on your kit or sweat that stings your eyes are signs of salty sweat.

Your hourly plan

Fluid per hour

250 to 800 mL

8.5 to 27 fl oz

Drink to thirst. The top number is a ceiling, not a goal. It stops at your estimated sweat loss.

Sodium per hour

370 to 1,660 mg

Estimated from your sweat loss and saltiness.

Carbs per hour

30 to 60 g

From drinks, gels or food combined.

Based on an estimated sweat loss of 800 to 1,200 mL (27 to 41 fl oz) an hour.

Notes on these numbers (4)
  • Sweat rate is estimated from ACSM predicted sweating rates for running. Weigh yourself before and after a session to get your own figure.
  • Drink to thirst. The fluid range stops at your estimated sweat loss because drinking more than you sweat raises the risk of low blood sodium (hyponatremia).
  • The sodium range is an estimate of what you lose in sweat, not an amount you must replace.
  • Sweat saltiness is unknown, so the sodium range is wide. A sweat test gives a personal figure.

Drinks that fit this plan

Ranked by how well a sensible number of servings an hour meets your sodium and carb targets without passing the fluid ceiling.

  1. Powerade

    Bottle Match 100/100
    Servings an hour
    2.2
    Drink an hour
    781 mL 26 fl oz
    Sodium an hour
    528 mg
    Carbs an hour
    46.2 g
    Cost an hour
    $0.91

    One serving: 12 fl oz (2.5 servings per 28 fl oz container), made up to 355 mL.

    • 2.2 servings an hour gives about 528 mg sodium, inside your 370 to 1,660 mg target.
    • Adds 46 g carbs an hour, inside your 30 to 60 g target.
    • That is 0.8 L of drink an hour; your fluid range is 0.3 to 0.8 L.

    Label checked . Source. Price checked at Target.

  2. Gatorade Endurance Formula Powder

    Powder tub Match 100/100
    Servings an hour
    2.2
    Drink an hour
    781 mL 26 fl oz
    Sodium an hour
    682 mg
    Carbs an hour
    46.2 g
    Cost an hour
    $1.67

    One serving: 1 1/2 scoops (24g), made up to 355 mL.

    • 2.2 servings an hour gives about 682 mg sodium, inside your 370 to 1,660 mg target.
    • Adds 46 g carbs an hour, inside your 30 to 60 g target.
    • That is 0.8 L of drink an hour; your fluid range is 0.3 to 0.8 L.

    Label checked . Source. Price checked at Gatorade (brand store).

  3. Skratch Labs Hydration Sport Drink Mix

    Powder tub Match 100/100
    Servings an hour
    1.6
    Drink an hour
    757 mL 26 fl oz
    Sodium an hour
    640 mg
    Carbs an hour
    32 g
    Cost an hour
    $1.92

    One serving: 1 scoop (22g), made up to 473 mL.

    • 1.6 servings an hour gives about 640 mg sodium, inside your 370 to 1,660 mg target.
    • Adds 32 g carbs an hour, inside your 30 to 60 g target.
    • That is 0.8 L of drink an hour; your fluid range is 0.3 to 0.8 L.

    Label checked . Source. Price checked at Skratch Labs.

  4. BASE Hydro

    Powder tub Match 100/100
    Servings an hour
    2.2
    Drink an hour
    781 mL 26 fl oz
    Sodium an hour
    616 mg
    Carbs an hour
    46.2 g
    Cost an hour
    $2.35

    One serving: 1 scoop (23g) (makes 12 fl oz), made up to 355 mL.

    • 2.2 servings an hour gives about 616 mg sodium, inside your 370 to 1,660 mg target.
    • Adds 46 g carbs an hour, inside your 30 to 60 g target.
    • That is 0.8 L of drink an hour; your fluid range is 0.3 to 0.8 L.

    Label checked . Source. Price checked at BASE Performance.

  5. Osmo Power Fuel

    Powder tub Match 100/100
    Servings an hour
    1.1
    Drink an hour
    781 mL 26 fl oz
    Sodium an hour
    451 mg
    Carbs an hour
    42.9 g
    Cost an hour
    $2.61

    One serving: 2 Rounded Scoops (42g), made up to 710 mL.

    • 1.1 servings an hour gives about 451 mg sodium, inside your 370 to 1,660 mg target.
    • Adds 43 g carbs an hour, inside your 30 to 60 g target.
    • That is 0.8 L of drink an hour; your fluid range is 0.3 to 0.8 L.

    Label checked . Source. Price checked at Osmo Nutrition.

  6. Precision Fuel & Hydration Carb & Electrolyte Drink Mix

    Powder tub Match 100/100
    Servings an hour
    1.6
    Drink an hour
    800 mL 27 fl oz
    Sodium an hour
    800 mg
    Carbs an hour
    48 g
    Cost an hour
    $3.41

    One serving: 2 level scoops (500 ml serving), made up to 500 mL.

    • 1.6 servings an hour gives about 800 mg sodium, inside your 370 to 1,660 mg target.
    • Adds 48 g carbs an hour, inside your 30 to 60 g target.
    • That is 0.8 L of drink an hour; your fluid range is 0.3 to 0.8 L.

    Label checked . Source. Price checked at Precision Fuel & Hydration (US store).

  7. Electrolit Electrolyte Hydration Beverage

    Bottle Match 100/100
    Servings an hour
    2.2
    Drink an hour
    781 mL 26 fl oz
    Sodium an hour
    550 mg
    Carbs an hour
    39.6 g
    Cost an hour
    $3.76

    One serving: 12 fl oz (360 mL); about 2 servings per 21 fl oz container, made up to 355 mL.

    • 2.2 servings an hour gives about 550 mg sodium, inside your 370 to 1,660 mg target.
    • Adds 40 g carbs an hour, inside your 30 to 60 g target.
    • That is 0.8 L of drink an hour; your fluid range is 0.3 to 0.8 L.

    Label checked . Source. Price checked at Target.

  8. Momentous Fuel

    Powder tub Match 100/100
    Servings an hour
    1.6
    Drink an hour
    757 mL 26 fl oz
    Sodium an hour
    480 mg
    Carbs an hour
    44.8 g
    Cost an hour
    $4.27

    One serving: 1 Scoop (33.1g), made up to 473 mL.

    • 1.6 servings an hour gives about 480 mg sodium, inside your 370 to 1,660 mg target.
    • Adds 45 g carbs an hour, inside your 30 to 60 g target.
    • That is 0.8 L of drink an hour; your fluid range is 0.3 to 0.8 L.

    Label checked . Source. Price checked at Momentous.

  9. SWORD Advanced Electrolyte Powder

    Powder stick Match 100/100
    Servings an hour
    3.3
    Drink an hour
    782 mL 26 fl oz
    Sodium an hour
    660 mg
    Carbs an hour
    49.5 g
    Cost an hour
    $5.94

    One serving: 8 fl oz (17g), made up to 237 mL.

    • 3.3 servings an hour gives about 660 mg sodium, inside your 370 to 1,660 mg target.
    • Adds 50 g carbs an hour, inside your 30 to 60 g target.
    • That is 0.8 L of drink an hour; your fluid range is 0.3 to 0.8 L.

    Label checked . Source. Price checked at SWORD Performance.

  10. Gatorade Endurance Formula (Ready to Drink)

    Bottle Match 100/100
    Servings an hour
    2.2
    Drink an hour
    792 mL 27 fl oz
    Sodium an hour
    682 mg
    Carbs an hour
    48.4 g
    Cost an hour
    Price not checked

    One serving: 12 fl oz (360 mL), made up to 360 mL.

    • 2.2 servings an hour gives about 682 mg sodium, inside your 370 to 1,660 mg target.
    • Adds 48 g carbs an hour, inside your 30 to 60 g target.
    • That is 0.8 L of drink an hour; your fluid range is 0.3 to 0.8 L.

    Label checked . Source.

How the hydration calculator works

The calculator estimates how much you sweat, then turns that into three hourly targets. Fluid stays at or below your sweat loss. Sodium is what that sweat is likely to carry. Carbs depend on how long you go. It then ranks drinks by how well they hit those numbers.

Sweat rate

Without a measured figure, the calculator starts from the American College of Sports Medicine (ACSM) table of predicted sweating rates for running, by body weight, pace and temperature.[6]Easy, moderate and hard map to the table's slower and faster paces. Your sweat level then widens or shifts that estimate. Most athletes sweat about 0.5 L/h to 2 L/h.[1]If you enter a measured sweat rate, it replaces the estimate.

Fluid

The top of the fluid range is the low end of your estimated sweat loss, so the calculator never suggests drinking more than you sweat. That follows the drink-to-thirst advice in the 2015 consensus statement on exercise-associated hyponatremia (low blood sodium).[5] The bottom of the range is the amount that keeps your total loss under 2% of body weight, the level ACSM links to worse performance.[6]

Sodium

Sweat holds about 10 mmol/L to 70 mmol/L of sodium, which is230 mg/L to 1,610 mg/L.[1] Your answer on saltiness picks a slice of that range: low uses 10 to 30 mmol/L, average 30 to 50 mmol/L and high50 to 70 mmol/L. Not sure uses 20 to 60 mmol/L, so the result is wider. Sweat rate times that concentration gives the hourly figure. It is an estimate of what you lose, not an amount you must replace. For sessions under an hour the target is zero, because water is usually enough.

Carbohydrate

Carbs follow session length, not sweat. Short sessions need none. From about one to two and a half hours the target is 30 g/h to 60 g/h, and longer sessions go up to90 g/h.[7][3]The higher amounts need a mix of glucose and fructose and some practice in training.

Drink matches

For each drink in our database, the calculator works out how many servings an hour reach the middle of your sodium range, capped so the volume stays under your fluid ceiling. Drinks score higher when that amount also lands inside your carb target. Nutrition comes from the label, and each result shows when we last checked it. Full details are on the methodology page.

How to use your result

  • Treat the numbers as a starting point for training, not race day. Try a plan on a long session first.
  • Drink to thirst. If you feel full or slosh, drink less, whatever the range says.
  • Count everything. Gels, chews and food add carbs and often sodium too.
  • Weigh yourself before and after a few sessions with the sweat rate calculator, then enter your measured rate for a personal plan.
  • Read how much sodium per hour to understand the sodium range, or browse every drink in the database with its full label.

FAQ

How much water should I drink per hour of exercise?

It depends on how much you sweat. Most athletes lose about 0.5 to 2 liters an hour. Drink to thirst, and do not drink more than you lose. This calculator's fluid range stops at your estimated sweat loss, so treat the top number as a ceiling rather than a goal.

How much sodium do I need per hour?

The calculator estimates how much sodium you lose in sweat. Sweat carries about 230 mg/L to 1,610 mg/L of sodium per liter, and a salty sweater loses far more than a light one. For sessions under an hour, water is usually enough. See our guide on how much sodium per hour.

How accurate is this hydration calculator?

It gives a starting estimate built from published averages. Two people of the same weight can sweat very different amounts. For a personal figure, weigh yourself before and after a session and use the sweat rate calculator. Then enter the measured rate here.

Why does the calculator show a range instead of one number?

Sweat rate and sweat saltiness vary from person to person and from day to day. A range is more honest than a single figure. Start in the middle, then adjust based on how you feel and on your weight change after training sessions.

Do I need a sports drink for a one-hour workout?

For most people, no. Under an hour, water is usually enough and the calculator shows no sodium target. Longer or hotter sessions are where sodium and carbohydrate start to matter. Our guide on whether you need electrolytes covers this in more detail.

How are the drink matches ranked?

For each drink, we work out how many servings an hour would reach the middle of your sodium range without going past your fluid ceiling. Drinks score higher when that amount lands inside your sodium and carb targets. Sodium counts for more than carbs, because carbs can also come from food. Ties go to the cheaper drink.