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Chlorine Dosing Calculator

Tell us your current free chlorine, your target, your gallons, and what kind of chlorine you use — we'll give you the exact amount to add.

Best for: Owners who buy their own chlorine and want to stop guessing.

Your pool

What are we dosing?

What kind of chlorine are you using?

Add this much

To raise FC by 2 ppm, add

1.6 fl oz

Liquid chlorine (12.5%)

How to add it safely

  • Add with the pump running.
  • Pour liquid chlorine slowly along the deep end.
  • Broadcast cal-hypo or dichlor evenly over the surface.
  • Trichlor tabs go in the skimmer or a floater — never on plaster.
  • Wait 30 min before retesting.

Free perk

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We'll save your inputs so you can re-run the dose next week without re-entering everything.

We'll email you the results and an occasional pool tip. No spam, unsubscribe with one click.