Fitness and training

Cycling Hydration

Cycling 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.

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Your details

Enter weight, extra for heat or exercise.

What is this calculator?

Cycling 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

Common questions

What is the cycling hydration calculator?

It turns weight, extra for heat or exercise into a cycling 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

Iona, Saturday 10K plan

Weight 72, Extra for heat or exercise 300

About 2.68 litres (4.7 pints). Extra heat or exercise still sits on top.

Graham, first parkrun

Weight 87.8, Extra for heat or exercise 366

About 3.26 litres (5.7 pints). Extra heat or exercise still sits on top.

Aoife, chasing a PB

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 cycling hydration, not a verdict. If the number worries you, take it to your GP rather than stacking new rules on yourself.

Fitness Reviewed

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.

Limitations

  • Illustration only.
  • Not personal medical advice.

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