Digital Logic Toolkit — Privacy
Privacy
No accounts, no server-side computation, and the two values stored on your device.
Last updated: 2026-08-01
The short version
There are no accounts. There is no server that does any of the work. Nothing you type into this site is ever transmitted anywhere. There is no advertising, no advertising network and no fingerprinting. There is one third-party script: Google Tag Manager, which loads Google Analytics 4 to count page views. It sees which pages are visited; it does not and cannot see your expressions, truth tables or any other input, because none of that leaves your browser. Two small preferences are stored on your own device so the site looks and behaves the way you left it.
What runs where
Every page on this site is a static file. Your browser downloads it once and then does all of the work locally: parsing your expression, running Quine–McCluskey, drawing the Karnaugh map, laying out the gate diagram, converting the number, computing the syndrome. There is no API to call, and there is no code path in this product that sends your input off your machine. If you disconnect from the network after your first visit, everything continues to work — that is not a fallback mode, it is the normal mode.
A consequence worth knowing: because state travels in the URL, a permalink such as …/boolean-simplifier/?expr=AB%2BA%27C contains your expression in plain text. That link only goes wherever you choose to send it, but if you paste it into a chat, a forum or a ticket, the expression goes with it.
What is stored on your device
Two values, in your browser’s localStorage, on this site’s origin only. We write nothing else: no sessionStorage, no IndexedDB records, and no Cache Storage beyond the offline copy described below. Google Analytics sets its own cookies (_ga and _ga_*) to tell a returning visit from a new one; those are Google’s, described in the analytics section below, and are not listed in the table.
| Key | Values | What it does | Cleared by |
|---|---|---|---|
| dlt-theme | light, dark, or absent (meaning: follow your system setting) | Remembers whether you chose light or dark, so the page does not flash the wrong colours on load. | Choosing “System” in the theme control, or clearing site data. |
| dlt-symbolset | ieee or iec | Remembers whether you want ANSI/IEEE distinctive-shape gate symbols or IEC 60617-12 rectangular ones, so every diagram matches your course. | Clearing site data. |
Neither value is an identifier, neither is sent anywhere, and neither can distinguish you from anyone else who made the same two choices. You can delete both at any time through your browser’s “clear site data” control, and the site will simply return to its defaults.
The offline copy
After your first visit, a service worker stores a copy of the site’s pages, styles and scripts in your browser’s Cache Storage so that it keeps working without a network. That cache contains only files we published; it never contains anything you typed. When a new version of the site is published, you will see an “Update available — reload” prompt rather than having the page change underneath you. Clearing site data removes the cache and the next visit re-downloads it.
Analytics
This site loads Google Tag Manager, which in turn loads Google Analytics 4, to answer one question: which pages people actually use. It records the page you are on, roughly where in the world you are, and the kind of device and browser — the ordinary page-view measurement. It does not receive your expressions, truth tables, Karnaugh maps or any other input, because that work never leaves your browser and there is no code path that sends it.
It runs on the live site only. Preview and staging deployments serve the identical files but the script checks the hostname and does nothing unless it is the real one, so our own testing never appears in the numbers. Blocking it — with an extension, a content blocker, or your browser’s tracking protection — has no effect on any tool, and the offline copy works whether or not the script ever loaded.
What we do not do
- No accounts, sign-in, email collection or newsletter.
- No logging of anything you type. The tools run entirely in your browser, so there is no server that could log an expression even if we wanted one.
- No advertising and no advertising network. Blocking the analytics script costs you nothing: every tool works identically with it blocked, and many readers will block it.
- No third-party fonts, embeds, CDNs or web-font services. Every asset that renders the page comes from this origin, and the typefaces are the ones already on your device. The one exception is the analytics script described above.
- No cookies of our own. The only cookies are Google Analytics’.
- No sale or sharing of personal data, and no data broker of any kind.
Hosting
The static files are served by Vercel Inc.. Like any web host, it processes the ordinary technical information a browser sends in order to deliver a file — your IP address, the requested path, your user agent — under its own privacy terms, which are linked here: https://vercel.com/legal/privacy-policy (opens in a new tab). We do not add anything to those requests, we do not receive an analytics feed from them, and we do not tie requests to individuals.
Links to other sites
The About page and several reference pages link to publishers, standards bodies and the RFC editor so you can read the primary sources. Those are ordinary outbound links; once you follow one you are on someone else’s site under their policy.
Children
This site has no accounts, asks for nothing, and receives nothing anybody types into it, at any age. It is intended for students at undergraduate level and above, and the only thing collected from a younger reader is the same anonymous page-view measurement described above.
Your rights
Data-protection rights such as access, correction, deletion and portability apply to personal data that an organisation holds about you. We hold no records that identify you: there is no account, no email address and no copy of anything you typed. The page-view measurement above is held by Google under its own terms; you can stop it reaching them at any time by blocking the script, and nothing on this site will behave differently. The two preferences live on your device and are under your control, not ours.
Changes to this page
If any of the above ever stops being true — if analytics, advertising or any third-party script is added — this page will be updated in the same release that makes the change, and the “Last updated” date will move. There is no version of this page that describes a state the site is not currently in.