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Dehydration Calculator

Assess your dehydration level with our dehydration calculator. Determine fluid loss and hydration deficit based on weight and activity. Get personalized rehydration recommendations.

Calculate Dehydration Level

Enter your body weight and fluid loss percentage to determine dehydration severity.

Our dehydration calculator uses standard medical formulas: Fluid Loss = Body Weight × Loss Percentage, Rehydration = Fluid Loss × 1.5. Calculations are based on clinical hydration standards and provide accurate dehydration assessments.

Dehydration Examples

See how dehydration levels vary by body weight and fluid loss percentage.

Mild Dehydration

Weight: 70 kg

Loss: 2%

Fluid Loss: 1.4 L

Rehydrate: 1.75 L

Severe Dehydration

Weight: 75 kg

Loss: 5%

Fluid Loss: 3.75 L

Rehydrate: 4.7 L

How to Use Dehydration Calculator

Follow these steps to assess your dehydration level.

1

Enter Weight

Your body weight

2

Select Loss %

Dehydration level

3

Calculate

Get fluid loss

4

Rehydrate

Follow guidance

Dehydration Tips

Use these tips to manage dehydration effectively.

  • Know the signs: Dehydration symptoms include thirst, dark urine, fatigue
  • Drink gradually: Rehydrate over time, not all at once
  • Add electrolytes: Use sports drinks for severe dehydration
  • Monitor weight: Track body weight changes during exercise
  • Prevent beforehand: Drink proactively before fluid loss occurs
  • Seek help: Severe dehydration needs medical attention
  • Stay informed: Use our calculator regularly for hydration tracking

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Explore other hydration and dehydration calculators.

FAQ – Dehydration Calculator

Questions about dehydration assessment.

Dehydration occurs when your body loses more fluid than it takes in, leading to inadequate water levels.
Dehydration is measured as a percentage of body weight lost through fluid loss.
Mild is 2% loss, moderate is 3%, severe is 5%, and critical is 7% or more body weight loss.
Rehydrate with 1.5 times the fluid loss amount over several hours, including electrolytes.
Yes! Athletes often experience significant fluid loss during exercise, making this calculator essential.
Seek medical help for severe dehydration with symptoms like dizziness, confusion, or rapid heartbeat.
Our dehydration calculator provides estimates based on standard formulas. Actual dehydration varies by individual.
Yes, our calculator is fully mobile responsive for on-the-go dehydration assessment.
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