POOL WATER LOSS TOOL

Evaporation Estimator

Estimate how much water your pool may normally lose to evaporation based on weather, surface area, and cover use.

Estimate Daily Evaporation

Rule-of-thumb estimator. Real evaporation varies with sun, wind, humidity, cover use, water temperature, and pool location.
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Estimated Daily Evaporation

Watch: Pool Evaporation & Leak Check Explained

Evaporation Estimator Guide

This calculator estimates daily evaporation using air temperature, water temperature, humidity, wind speed, pool surface area, and cover usage. The result is a practical estimate, not an exact measurement.

Why It Matters

  • Estimate normal water loss.
  • Spot possible leaks when water loss is excessive.
  • Plan makeup water usage.
  • Reduce unnecessary chemical dilution.

Typical Water Loss

Many pools lose about 1/8 to 1/4 inch per day during warm weather. Hot, windy, dry conditions can produce significantly higher evaporation, while a quality cover can greatly reduce water loss.

Common Mistakes

  • Assuming every drop in water level is evaporation.
  • Ignoring splash-out and backwashing.
  • Not considering wind and humidity.
  • Forgetting that leaks can mimic evaporation.
Pool Gal Pro Tip 💦
If you're adding water every few days, compare estimated evaporation with actual water loss. If the numbers don't match, run a bucket test before assuming the weather is responsible.
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