Jo, race-week carbs
Weight 72, Extra for heat or exercise 300
About 2.68 litres (4.7 pints). Extra heat or exercise still sits on top.
Sweat Loss Hydration
Sweat Loss Hydration takes weight, extra for heat or exercise and turns them into a number you can read in one sitting. A simple 33 ml per kg sketch, plus any extra you add. It is a quick sense check in the browser, not a diagnosis.
Your details
Enter weight, extra for heat or exercise.
What is this calculator?
Sweat Loss Hydration takes weight, extra for heat or exercise and turns them into a number you can read in one sitting. A simple 33 ml per kg sketch, plus any extra you add. It is a quick sense check in the browser, not a diagnosis.
How it works
- Enter weight, extra for heat or exercise in the units on the form.
- We apply the method described under the result.
- Read the number as a sketch. If it worries you, take the original figures to a GP.
Common questions
What is the sweat loss hydration calculator?
It turns weight, extra for heat or exercise into a sweat loss hydration figure you can read in one sitting. Use it as a guide, not a diagnosis.
Does this replace my GP?
No. The maths stays in your browser. Speak to a GP if you are worried about your health.
Can I treat the number as a target?
Treat it as a planning figure. Real weeks wobble. If a goal feels extreme, stop and get proper advice.
Example scenarios
Clare, reading a label
Weight 87.8, Extra for heat or exercise 366
About 3.26 litres (5.7 pints). Extra heat or exercise still sits on top.
Duncan, after a takeaway Friday
Weight 56.2, Extra for heat or exercise 234
About 2.09 litres (3.7 pints). Extra heat or exercise still sits on top.
Understanding your results
Treat this as a snapshot for sweat loss hydration, not a verdict. If the number worries you, take it to your GP rather than stacking new rules on yourself.
About this result
Guidance only. Calculations run in your browser. Numbers are estimates, not a diagnosis.
How we calculate
A simple 33 ml per kg sketch, plus any extra you add.
Sources
Limitations
- Illustration only.
- Not personal medical advice.
Spotted an error? Request a correction or read our editorial policy.