Pool Volume & Chlorine Dose Calculator (Free)

Q: What free chlorine level should I run?

Most pools maintain 1–3 ppm for daily use; shock levels are commonly 8–12 ppm. Always test and follow product labels.

Q: How do I estimate average depth?

Take shallow and deep measurements and average them. For irregular shapes, sample multiple points and average.

Q: What if my pool is kidney-shaped?

Choose the closest shape (oval or rectangle) and use representative length, width, and average depth. Treat the result as an estimate and retest water.

Q: Does this work for salt pools?

Yes. Salt pools still target a free chlorine ppm. Salinity (salt ppm) is separate and not part of this calculator.

Use this free calculator to work out your pool volume and how much chlorine to add for daily maintenance or a shock. Supports metric (m, L) and imperial (ft, gal) and common pool shapes (rectangle, round, oval).

How to use the calculator

Choose units (Metric or Imperial).
Select pool shape (Rectangle, Round, or Oval).
Enter dimensions and your average depth (see tip below).
Pick chlorine product and set your target free chlorine (ppm).
Click Calculate to see your volume and dosing amounts.

Tip – average depth: (Shallow depth + Deep depth) ÷ 2. For irregular shapes, take 3–4 measurements around the pool and average them.

Worked example

Rectangle pool: 10 m × 4 m × 1.5 m average depth

Volume: 60,000 L
To reach 2 ppm (maintenance) with Cal-Hypo 65%: ~185 g
Shock to 10 ppm with Cal-Hypo 65%: ~923 g
Liquid 12.5%: ~0.80 L (2 ppm) or 4.00 L (10 ppm)

Common mistakes to avoid

Guessing depth: measure shallow and deep ends; use the average.
Wrong units: double-check m vs ft (and L vs gal).
Over-rounding: small volumes can swing dose accuracy—enter one or two decimals.
Not testing water: always test with a reliable kit and follow product labels.

Pool dosing FAQs

What free chlorine level should I run?

Most pools maintain 1–3 ppm day-to-day. Shock levels are commonly 8–12 ppm. Always test water and follow product guidelines.

How do I estimate average depth?

(Shallow depth + Deep depth) ÷ 2. For non-uniform shapes, sample multiple spots and average.

What if my pool is kidney-shaped?

Pick the closest shape (oval or rectangle) and use representative length, width, and average depth. The result is an estimate—dose conservatively and retest.

Does this work for salt pools?

Yes. Salt systems still maintain a target free chlorine (ppm). (Salinity in ppm is separate and not part of this calculator.)

Pool volume calculator

Use the tool below to calculate your exact volume and chlorine dose:

Next: Need pump run-time? Try our Pool Pump Turnover & Daily Run-Time Calculator.