- Everything here is free and provided as information, not as a professional pool service.
- We work hard to be accurate — and you should still follow the label on the bottle.
- Never mix pool chemicals with each other. That rule outranks anything a calculator tells you.
- Your pool is your responsibility. We can't see it, test it, or know what's in it.
Who these terms are with
PoolToolbox (pooltoolbox.com) is operated by Hamilton Digital Media Limited, registered in England and Wales under number 15608219, registered office 13a Mill Lane, Wimborne, Dorset, United Kingdom, BH21 1LN. In these terms, "we" and "us" mean that company. By using the site, you're agreeing to what follows.
What this site is
A set of free calculators and guides for maintaining a swimming pool or spa. There's nothing to buy from us, no account to create, and no subscription. You can use the tools for your own pool, or for pools you service professionally, at no charge.
What we promise about the math — and what we don't
We take the numbers seriously, because they're the entire point of the site. Every dose is derived from published industry formulas rather than copied from someone else's table. All the calculators share one calculation engine, so they can't disagree with each other. That engine is covered by an automated test suite checked against reference values, and every result has a "show the math" panel so you can follow the arithmetic yourself.
What we can't do is see your pool. A calculator only knows what you type into it, and the most common source of a wrong dose isn't our arithmetic — it's a pool volume that was estimated rather than measured, a test kit that's out of date, or a product whose strength differs from the label. So we provide the math without a warranty that a given result is correct for your specific pool, and you remain responsible for sanity-checking the dose before you add anything to water. If a result looks wrong, it might be — please tell us.
- Never mix pool chemicals together, in a bucket, a scoop, or storage. Chlorine and acid combined release chlorine gas, which can be fatal.
- Always add acid to water, never water to acid, and pour slowly with the pump running.
- Add one chemical at a time, letting each circulate before the next.
- The product label wins. If a manufacturer's instructions differ from anything here, follow the manufacturer.
- Store chemicals separately, dry, and out of reach of children and pets.
This isn't professional advice
The site is general information, not tailored advice for your pool, and using it doesn't create a professional relationship between us. For structural problems, equipment installation, gas work, electrical work, or anything about the health of people using the pool, consult a qualified professional. If you think someone has been harmed by pool water or chemicals, contact a doctor or your local emergency service — not a calculator.
What stays your responsibility
- Measuring your pool volume properly, since every dose scales from it.
- Testing your water with a kit in good condition, and retesting after dosing.
- Reading and following the labels on the products you actually buy.
- Complying with local rules on draining, backwashing, and chemical disposal.
- Deciding whether a given result makes sense for your pool before acting on it.
Links to other sites
We link out to retailers, manufacturers and reference sources. Some of those are affiliate links, explained in full in our affiliate disclosure. We don't control other websites and aren't responsible for their content, their products, or their privacy practices — once you leave here, their terms apply.
Content and copyright
The writing, design, code and calculator implementations on this site belong to us. You're welcome to use the tools, quote us with credit and a link, and print or save results for your own use. Please don't republish our articles wholesale, copy the calculators onto another site, or scrape the site automatically.
To be clear about what we're not claiming: the underlying chemistry is public knowledge and nobody owns it. Molecular weights, saturation index formulas and the industry dosing relationships are free for anyone to use — it's our particular expression of them that's covered.
Availability
We aim to keep the site up and current, but it's provided as-is. We may change, move or retire tools and articles, and we don't guarantee uninterrupted access.
Liability
To the extent the law allows, we're not liable for loss or damage arising from your use of this site — including damage to a pool or its equipment, the cost of chemicals or water, or losses from acting on a result without checking it.
Nothing in these terms limits or excludes our liability for death or personal injury caused by our negligence, for fraud, or for anything else that can't lawfully be excluded. If you're a consumer, you keep all the statutory rights you have where you live, and nothing here takes them away.
Governing law
These terms are governed by the laws of England and Wales, and disputes fall to its courts. If you use the site as a consumer somewhere else, you keep the protection of any mandatory consumer law that applies where you live.
Changes
We may update these terms as the site grows. The date at the top of this page shows when they last changed materially, and continuing to use the site means the current version applies.
Contact
Questions about these terms: [email protected]. Something here that's factually wrong: [email protected].