Pool & Hot Tub Chemical Calculator

Instantly calculate chlorine and pH adjustments for pools and hot tubs.

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Tools

Pool Volume Calculator

Enter dimensions to get your pool or hot tub volume in gallons.

Chlorine Calculator

Calculate how much chlorine to add based on your test results.

pH Calculator

Adjust pH with increaser or reducer based on current levels.

Pool Water Balance Charts

Pool Chemical Levels Chart

Ideal ranges for chlorine, pH, alkalinity, and stabilizer in one view.

Chlorine Levels Chart

Daily vs shock chlorine targets and how to read your tests.

pH Levels Chart

Target bands and why pH matters for sanitizer and comfort.

Pool Chemistry Reference

Ideal ranges, low/high effects, and calculator links for every parameter.

Frequently Asked Questions

What chlorine level should my pool be?

For swimming pools, aim for 1–3 ppm chlorine. For hot tubs and spas, 3–5 ppm is recommended.

What is the ideal pH for pool water?

Keep pH between 7.2 and 7.6 for pools, and 7.2–7.8 for hot tubs. This range is safe for skin and equipment.

How often should I test my pool water?

Test chlorine and pH at least 2–3 times per week. Test alkalinity and other parameters weekly.

Can I use the same chemicals for pools and hot tubs?

Many chemicals are the same, but hot tubs need higher chlorine (3–5 ppm) and you should use spa-specific products when recommended.

Last updated: April 2026