CYA / Stabilizer Calculator

Calculate how much granular cyanuric acid to add to reach your target CYA.

Use the Pool Volume Calculator if you’re not sure.
If you’re unsure, leave this at 100%.
Add approximately:

Important before adding stabilizer

  • CYA is difficult to remove once it is in the pool.
  • Add in stages rather than overshooting your target.
  • Allow the product to dissolve and circulate before retesting.
  • Follow the product label for the safest addition method.
💡 Tip: It is much easier to add a little more CYA later than to remove too much.

Watch: Pool CYA Stabilizer Calculator

How to Raise Cyanuric Acid in Your Pool

Cyanuric acid, usually called CYA, stabilizer, or conditioner, protects chlorine from being destroyed too quickly by sunlight. This calculator estimates how much granular cyanuric acid to add based on your pool volume, current CYA reading, and target level.

Granular stabilizer dissolves slowly, so follow the product label and allow the product to dissolve and circulate fully before relying on the next test result.

Why Pool Stabilizer Matters

Outdoor pools need enough CYA to slow the loss of free chlorine caused by ultraviolet sunlight. With little or no stabilizer, chlorine can disappear rapidly on a bright summer day.

More CYA is not always better. As CYA rises, the pool generally needs a higher free-chlorine level to remain properly sanitized. Excessive CYA can make chlorine management difficult and may require water replacement.

Recommended CYA Levels

Many traditionally chlorinated outdoor pools are maintained around 30–50 ppm CYA. Saltwater chlorine-generator pools often operate higher, commonly around 60–80 ppm, depending on manufacturer guidance and operating conditions.

Common Stabilizer Mistakes

  • Adding stabilizer without confirming the current CYA level.
  • Guessing the pool volume and accidentally overdosing.
  • Raising CYA too far in one treatment.
  • Retesting before the stabilizer has fully dissolved and circulated.
  • Using stabilized chlorine products without accounting for the CYA they add.
Pool Gal Pro Tip 💦
If your test shows CYA near the top of your acceptable range, stop before adding more. Confirm the test and pool volume first.
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Accuracy & Dosing Caution

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Stabilizer (CYA) Splash Sheet

A quick-reference printable for CYA targets, chlorine protection, and poolside use.

VIEW SPLASH SHEET