- Everything here is free and provided as information, not as professional or legal advice.
- We work hard on the math — and your hydrometer still has the final say.
- Never bottle a beer that hasn't finished fermenting. That rule outranks anything a calculator tells you.
- Brewing is for adults of legal drinking age, and these tools are for beer, wine, mead and cider — not distilling.
Who these terms are with
BrewToolbox (brewtoolbox.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 homebrewing beer, and for the closely related arithmetic of mead, cider and wine. There's nothing to buy from us, no account to create, and no subscription. You can use the tools for your own brewing, or in a commercial brewery, at no charge — though anything at commercial scale deserves instruments and procedures a homebrew calculator isn't a substitute for.
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 result comes from a published formula — Tinseth, Rager, Palmer's infusion equations, the ASBC methods — cited on the page it appears on, rather than copied from someone else's table. All the calculators share one calculation engine, so two pages can't disagree about the same wort. That engine is covered by an automated test suite checked against published 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 brewery. A calculator only knows what you type into it, and the commonest source of a wrong answer isn't our arithmetic — it's a volume that was estimated rather than measured, a hydrometer reading taken warm, an alpha-acid figure from a packet that's been in a warm cupboard for a year, or an efficiency number borrowed from someone else's system.
It's also worth being plain that several of these formulas are fits, not physics. Tinseth and Rager disagree with each other by a third on a bittering addition. Refractometer corrections are regressions over other people's beers. Pitch rates are a range, not a number. We show that disagreement rather than hide it, but it means we provide the math without a warranty that a given result is correct for your batch, and you remain responsible for sanity-checking a number before you act on it. If a result looks wrong, it might be — please tell us.
- Never bottle beer that is still fermenting. Confirm a stable final gravity across readings several days apart before you add priming sugar. Bottles that keep fermenting become pressure vessels, and glass that fails does so violently.
- Prime by weight, not by guess, and use bottles rated for carbonation. If a batch may be over-primed, chill it and open the bottles slowly, somewhere the glass can't hurt anyone.
- Treat kegs, cylinders and regulators as pressure equipment. Never exceed a vessel's rated pressure, secure CO₂ cylinders upright, and don't modify fittings.
- Boiling wort burns. Twenty-odd liters of it at a rolling boil, and a boil-over, deserve more caution than anything else in a kitchen. Burners belong outdoors — never run a propane burner indoors or in a garage.
- Never mix cleaning chemicals. Acid sanitizers and bleach together release chlorine gas. Follow the label on every cleaner and sanitizer, and keep them away from children and pets.
- The product label wins. If a manufacturer's instructions differ from anything here, follow the manufacturer.
Alcohol, age and the law
This site is for adults of legal drinking age where they live. It isn't directed at children, and nothing here is an encouragement to drink to excess — brew responsibly and drink responsibly.
Making beer, wine, mead and cider at home for personal use is legal in most places, but the details are local: some jurisdictions cap the annual volume, some require it stay on your property, and selling what you make almost always requires a license. Checking what applies where you are is your responsibility, not ours.
These calculators are for fermentation, not distillation. Distilling spirits at home without a license is illegal in the United States and many other countries. We don't provide distilling calculations, instructions or encouragement, and where a tool mentions spirits — such as fortifying a batch — it means a bottle you bought.
This isn't professional advice
The site is general information, not tailored advice, and using it doesn't create a professional relationship between us. For gas work, electrical work, pressure-vessel certification, food-business licensing, or anything about the health of people drinking what you make, consult someone qualified. If you think someone has been harmed — by an injury, by alcohol, or by something they drank — contact a doctor or your local emergency service, not a calculator.
What stays your responsibility
- Measuring your volumes properly, since nearly every number here scales from them.
- Correcting hydrometer readings for temperature, and confirming a stable final gravity before packaging.
- Reading and following the labels on the yeast, chemicals and equipment you actually buy.
- Sanitation — no calculator can tell you whether the fermenter was clean.
- Complying with local law on making, storing, transporting and (not) selling what you brew.
- Deciding whether a given result makes sense for your system 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 and charts for your own brewing. 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 brewing science is public knowledge and nobody owns it. Tinseth's utilization formula, Palmer's infusion equations, the ASBC's methods and the standard gravity relationships are free for anyone to use — it's our particular expression of them, and the words around them, that are 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. Your equipment profile lives in your own browser, so if the site were to disappear tomorrow, your data would still be yours — and equally, we can't restore it for you if your browser clears it.
Liability
To the extent the law allows, we're not liable for loss or damage arising from your use of this site — including a ruined batch, wasted ingredients, damage to equipment, 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].