Pool Calculator
Free pool calculator. Work out pool volume in gallons and litres for a rectangular or round pool, plus chlorine, alkalinity and calcium dosage estimates.
About This Free Online Pool Calculator
Our free pool calculator works out your swimming pool volume in gallons and litres from its shape and dimensions, then gives quick chemical dosage estimates to raise free chlorine, total alkalinity and calcium hardness. Enter the length, width (or diameter) and average depth in feet for a rectangular or round pool and the tool returns the volume plus the bleach, baking soda and calcium chloride amounts to nudge each level. Doses are industry-rule-of-thumb estimates — always confirm against your test kit. Everything runs in your browser with no signup.
Features of Our Pool Calculator
- Volume in gallons and litres for rectangular or round pools
- Average-depth input for sloped or hopper bottoms
- Chlorine dose estimate (6% bleach, fl oz and cups)
- Alkalinity and calcium hardness dose estimates
- Great for opening, closing and routine balancing
- 100% client-side and private — no signup, no data sent
How to Use the Pool Calculator
Using this tool is simple and requires no signup or registration. Follow these steps:
- Choose Rectangular or Round and enter the dimensions in feet.
- Enter the average depth (shallow + deep end divided by 2 for a slope).
- Read the pool volume in gallons and litres.
- Use the chemical estimates as a starting dose and re-test.
Frequently Asked Questions About Pool Calculator
How do I calculate my pool volume in gallons?
For a rectangular pool, multiply length × width × average depth (all in feet) to get cubic feet, then multiply by 7.48 to convert to gallons. For a round pool, use π × radius² × depth × 7.48. This calculator handles both.
What average depth should I use?
For a pool with a shallow and a deep end, average depth is (shallow end + deep end) ÷ 2. A flat-bottom pool just uses its one depth. Enter the result in feet.
How much chlorine does my pool need?
To raise free chlorine by about 1 ppm, the calculator estimates roughly 25.7 fl oz of 6% household bleach per 10,000 gallons. Actual need depends on your current level, CYA and bather load — always test and adjust.
Are the chemical doses exact?
No — they are widely used starting estimates (bleach for chlorine, baking soda for alkalinity, calcium chloride for hardness). Always confirm with a reliable test kit and the product label before dosing.
Is this pool calculator free?
Yes, completely free with no signup. Every calculation runs in your browser, so nothing is uploaded or tracked.
Why Choose Text Toolbox?
Text Toolbox provides free, private, and instant online text tools. Unlike other text utility websites that require signup accounts or send your data to servers, all our tools process your text entirely in your browser. This means your content never leaves your device — we cannot see it, store it, or share it. Our tools are fast, lightweight, and work on any device with a modern web browser.