Free Tool · Nutrition & Body Goals

Hydration & Electrolyte Calculator

A daily water target, extra fluid for training days, and when to add electrolytes.

How we calculate: 35 ml per kg of body weight, plus extra for sweat lost in training and more in hot weather. Everyone sweats differently — adjust for your client, and check with a doctor if they have kidney problems.

Body Weight (kg)

Workout Duration (mins)

Training Intensity

Climate

Daily hydration plan

Total Target

3.5L

3548 ml / day

Standard Glasses

250ml servings

Hourly Pace

~222

ml / awake hour

Extra for Training

+600

ml for training

When to drink around workouts

• Before: Sip 400–500 ml of water 1.5–2 hours before training.
• During: Drink 150–250 ml every 15–20 minutes of hard training.
• After: Drink 1.25–1.5× the sweat lost, over the next 2 hours.

Electrolyte Replenishment

Long or hot sessions lose more salt. Add 300–500 mg of sodium (a pinch of salt or an electrolyte tablet) to post-workout water to rehydrate faster.