Privacy policy

Last updated: 2026-10-06

World Jan is operated by widewell. This policy explains what happens to data when you play. In short: there are no accounts and the game runs entirely in your browser. The site is funded by ads from Google, which uses cookies. Our own statistics contain no IP address, browser identifier or any ID.

Data stored on your device

The game may save your settings, your statistics and an unfinished match in your browser's local storage. They stay on your device and are never sent to us. Clearing your browser data deletes them.

Anonymous usage statistics

To understand how the game is played, your browser sends anonymous events when you start a match, finish a hand, finish a match or press share. Each event contains only: the event type, the interface language, the CPU level, the result of the hand or match (win, loss or draw, Tsumo or Ron, the yaku, the points and how many turns you took), your final score and the number of hands, and the country inferred by our CDN. We do not store IP addresses, browser identifiers or any ID that links events to you. Events are kept for up to 400 days and used only in aggregate.

Google Analytics

The site also uses Google Analytics (Google LLC) to measure how many people visit and which pages they view. It uses cookies (_ga and _ga_*, up to 2 years) and receives your IP address, the address of the page, and browser and device details. Google Analytics does not log or store IP addresses itself. In the EEA, the UK and Switzerland it stores nothing on your device until you consent in Google's message (see below). Learn more in how Google uses information from sites that use its services. To opt out everywhere, install the Google Analytics opt-out browser add-on.

Advertising

Some pages show ads served by Google AdSense, and the game may show a full-screen ad between hands. Third-party vendors, including Google, use cookies to serve ads based on your prior visits to this website or other websites. Google's use of advertising cookies enables it and its partners to serve ads to you based on your visits to this site and/or other sites on the Internet. See how Google uses information from sites that use its services.

Cookies used for ads include __gads and __gpi (up to 13 months) and __eoi (up to 6 months) on this site, and IDE (13 months in the EEA and the UK, 24 months elsewhere) and test_cookie (15 minutes) on doubleclick.net. Google lists them in its advertising cookie list. Ads may also be served by other ad technology providers that Google works with; see Google's list of ad technology providers.

You can opt out of personalised advertising in Google's Ads Settings, and opt out of some third-party vendors' personalised advertising at www.aboutads.info (in Europe, www.youronlinechoices.eu).

Consent in the EEA, the UK and Switzerland

If you visit from the European Economic Area, the United Kingdom or Switzerland, Google asks for your consent before cookies are used for ads and analytics, through a message certified under the IAB Transparency and Consent Framework. Without consent, Google shows limited ads that do not use personal data for personalisation, and Google Analytics stores nothing on your device. You can change or withdraw your consent at any time:

Information sent to third parties

As required by Japan's Telecommunications Business Act, this is what the site has your browser send to others.

Service providers

The site runs on Google Cloud (hosting and statistics storage, in the United States) and is delivered through Cloudflare (content delivery and protection against abuse). These providers process your IP address to deliver the site. Our hosting provider's standard request logs include IP addresses; they are kept for up to 30 days for security and troubleshooting and are not used for statistics.

Contact

Questions about this policy: contact@worldjan.com