UnityLife

Hydration

Dehydration risk calculator

Quick screen for dehydration severity. Uses Armstrong urine-colour chart, body-weight change, and a symptom checklist. Educational — not a clinical diagnosis.

Free tool
Symptoms (check all that apply)

Dehydration risk

Low(score 0/11)

Keep sipping water through the day. No corrective action needed.

Educational screening — not a clinical diagnosis. Severe symptoms (confusion, no urination for 8+ hours, fainting, infant or older adult with poor intake): call 811 or seek medical care.

Scoring blends Armstrong’s urine colour chart (urine 5+ = mild dehydration), the ACSM hydration position (1 % body-weight loss starts to affect performance, 3 %+ is meaningful dehydration), and a simple symptom tally. Use it as a self-check, not a diagnosis. Sources: Armstrong (1994); ACSM Position Stand on Exercise and Fluid Replacement (Sawka et al. 2007); Health Canada hydration guidance.

How the score works

The score blends three established markers: urine colour (Armstrong 1994 chart, score 5+ indicates mild dehydration), body-weight change (3 %+ loss is meaningful per the ACSM 2007 hydration position stand), and a symptom tally. The bands are tuned to point you toward proportionate action — water and a salty snack at “mild”, an oral rehydration solution at “moderate”, medical care at “high”.

Recovery basics

For mild–moderate dehydration: 250–500 mL of water with 1/4 tsp of salt or a pre-made oral rehydration solution (ORS — Pedialyte, Gastrolyte, or homemade with 1 L water + 6 tsp sugar + 1/2 tsp salt). Re-check urine colour in 1–2 hours. For severe dehydration or symptoms in vulnerable people (infants, frail elders, pregnant), seek medical care.

When this calculator is wrong

Vitamin B2 supplements turn urine bright yellow regardless of hydration. Beets and certain medications can darken urine. Diabetes insipidus, diuretic medications, and kidney disease all affect urine colour as a hydration marker. Use this tool as a first-pass check, not a diagnostic.

This tool is for educational purposes only and does not provide medical advice, diagnosis, or treatment. Always consult a licensed Canadian healthcare professional. Read our full disclaimer.