Privacy Policy for Engine Calculator

This Privacy Policy explains how Engine Calculator (“we”, “us”, or “our”) handles information when you visit Engine-Calculator.com and use our engine calculators — including the compression ratio tool.

The short version: the numbers you enter — bore diameter, stroke length, chamber cc, gasket thickness, piston dome or dish volume, deck clearance, intake valve closing angle, connecting rod length, altitude, and octane grade — are computed entirely by JavaScript running in your browser. They are never transmitted to, stored on, or even seen by our servers. We collect only the standard, anonymized analytics any website needs to stay online and improve.

Every number you type into the calculator is a local event. The engine — the swept volume formula, clearance volume summation, slider-crank geometry, static and dynamic compression ratio calculations, octane range lookup, and reverse target-solver math — runs on your device, in your browser tab, with no network call attached to it.

We do not transmit, log, aggregate, or read your engine project values. There is no “saved builds” history on our side to subpoena, sell, or leak, because none exists. If you close the tab, the inputs are gone unless your browser itself kept a locally stored preference for convenience (see Cookies & Local Storage below).

Server Logs & Technical Data

When you request any page, our hosting layer may automatically record:

• Your IP address (used only for approximate country/region and abuse prevention, never to identify you)
• Browser type, version, and device category
• Pages requested, timestamps, and response sizes
• The referring site or search query that brought you here

Messages You Send Us

If you email support or submit a correction, we receive whatever you choose to include — for example, the inputs you were testing, a screenshot of the results panel, and your email address so we can reply. We use it solely to answer you and to fix whatever you reported.

We use a minimum of browser storage, and only for two purposes:

• Site functionality: remembering interface preferences (such as your last-selected unit system or decimal places) so the calculator feels continuous between visits.
• Advertising & analytics: third-party cookies from our ad and analytics providers, described in the sections below.

You can clear or block all cookies in your browser settings; the calculator will still work, because none of the compression ratio math depends on cookies.

This site is free because advertising pays for it. We use third-party advertising vendors, including Google AdSense, to serve ads. These vendors may use cookies (including the Google advertising cookie) to serve ads based on your prior visits to this or other websites.

• Google’s use of advertising cookies enables it and its partners to serve ads to you based on your visit to our site and/or other sites on the Internet.
• You may opt out of personalized advertising by visiting Google Ads Settings , or opt out of many third-party vendors’ cookies at aboutads.info .
• Where required by law (EEA, UK, Switzerland, and certain U.S. states), a consent banner lets you accept or reject personalized advertising before ad scripts load.

Ads are clearly separated from calculator output and editorial content. We do not control which ads appear and do not endorse advertised products.

We use Google Analytics (GA4) to collect privacy-conscious, aggregate analytics — page views, session duration, referrers, approximate region, and device type — to understand which calculators and guides are useful. We do not attempt to identify individuals, and we do not build behavioral profiles across other websites.

We share information only in these narrow cases:

• Service providers: hosting, analytics, and advertising vendors that process data on our behalf under contract
• Legal requirements: when compelled by valid legal process from competent authorities
• Site protection: to investigate abuse, attacks, or fraud affecting the service
• Business transfer: if the site is ever merged or acquired, with notice via this page

Server logs are retained for a short operational window (typically 30–90 days) and then rotated or anonymized. Analytics data is kept in aggregate form. Emails you send us are retained only as long as needed to resolve your question and improve the tool, then deleted.

Because your compression ratio calculation inputs never leave your device, the most sensitive data on this site has no server-side footprint to protect. For what little we do hold, we use HTTPS everywhere and reputable infrastructure providers. No method of transmission over the Internet is 100% secure, but the architecture minimizes what could ever be exposed.

Depending on where you live, you may have rights under laws such as the GDPR/UK GDPR, the California Consumer Privacy Act as amended (CCPA/CPRA), and similar regulations:

• Request access to, correction of, or deletion of personal data we hold about you
• Object to or restrict certain processing, or withdraw consent where processing is consent-based
• Opt out of the “sale” or “sharing” of personal information for cross-context behavioral advertising — which you can do any time via the ad opt-out links above or our consent banner
• Non-discrimination for exercising any of these rights

To exercise any right, email us with enough detail to verify your request. Because we hold so little personal data, most requests resolve within days.

This site is intended for a general audience — engine builders, machinists, cam grinders, tuners, automotive educators, and adults planning performance engine projects — and is not directed to children under 13 (or under 16 in the EEA). We do not knowingly collect personal information from children. If you believe a child has provided us personal information, contact us and we will delete it promptly.

We may update this policy to reflect changes in the site, vendors, or law. Material changes will be noted with a new “last updated” date at the top of this page, and the current version is always linked in the site footer.

Questions about this policy? Reach us through the contact page or email privacy@Engine-Calculator.com — we read everything.