Last updated: 2026-08-16.
This policy explains what information GravityBench (at gravitybench.com) collects, why, and what your choices are. If you have a question this page doesn't answer, contact us at contact@gravitybench.com.
The calculators don't send your numbers anywhere
Every calculator on this site — ABV, IBU, priming sugar, dilution and blending, strike water, and SRM colour — runs entirely in your browser using JavaScript. When you type a gravity reading, a hop weight, or a grain bill into a tool, that number is processed on your own device and never transmitted to our servers, logged, or stored by us in any form. The only place your inputs go is into the page's own URL (so you can bookmark or share a specific result), which stays entirely within your browser and whatever service you choose to share that link through.
Information we do collect
Email address, if you choose to give it to us. If you use the "email me this result" option on a calculator page, subscribe to updates, or use the contact form, we collect the email address you provide. We use this to send the specific thing you asked for (a copy of a calculation result, a reply to your message, or periodic updates if you've subscribed) and nothing else. We do not sell, rent, or share your email address with third parties for their own marketing purposes.
Standard web analytics. Like most websites, we use analytics tools (which may include Google Analytics and Vercel's built-in analytics) to understand aggregate traffic patterns — which pages are visited, roughly how long people stay, and what device/browser categories are common. This data is aggregated and is not used to identify you individually. These tools may set cookies or use similar technologies; you can block them using your browser's privacy settings or a browser extension without losing access to any calculator or reference page on the site.
Contact form submissions. If you use the contact form, the message and email address you provide are transmitted to a third-party form-processing service (Formspree) and then to us, solely to respond to your message.
Server logs. Like virtually every website, our hosting provider (Vercel) automatically logs basic technical information (IP address, browser type, pages requested, timestamps) for security and operational purposes. We do not actively review these logs to identify individual visitors.
Advertising
This site carries ordinary display advertising served through Google AdSense to help cover hosting costs — no post is sponsored, no reference page is paywalled, and no advertiser sees a page before it's published. AdSense and its partners may use cookies or similar technologies to personalise the ads you see, based on your visits to this and other websites. You can review and control this at Google's My Ad Center (for a signed-in Google account), or opt out of interest-based advertising more broadly through the Digital Advertising Alliance's consumer choice page.
Payment information
If you purchase the Brew Day Pack or make a donation, payment is processed entirely by Stripe. We do not receive, see, or store your full payment card details — Stripe handles that directly, under its own privacy policy and PCI-compliant infrastructure. We receive only confirmation that a payment succeeded and the email address associated with it, for the purpose of fulfilling your purchase.
Your choices
You can decline to provide an email address anywhere on this site and still use every calculator and reference page in full. You can ask us to delete any email address we hold for you, or ask what data we hold, by writing to contact@gravitybench.com. We will respond within a reasonable time.
Children's privacy
This site's subject matter — homebrewing beer, cider and mead — concerns an activity restricted to adults of legal drinking age in most jurisdictions, and the site is not directed at children. We do not knowingly collect personal information from anyone under 13.
Changes to this policy
If this policy changes materially, we will update the "Last updated" date above. Continued use of the site after a change constitutes acceptance of the revised policy.
Data retention
We retain email addresses collected through the newsletter or result-email feature for as long as you remain subscribed, or until you request deletion. Contact form submissions are retained only as long as needed to resolve your inquiry. We do not retain calculator inputs at all, because they are never transmitted to us in the first place.