Privacy policy

Effective 24 September 2026

This policy explains what information Mahjong (mahjong.haus) collects, how it is used, and the choices you have. The site is run by KabKolor. If you have any questions, contact us at karl@kabkolor.com.

Playing as a guest

You can play without an account. So that a guest can still save a win by signing in afterwards, our server deals and times each guest game and checks the result, just like a signed-in game. A guest game isn't linked to you or your device: it's identified only by a random code kept in your browser. If you sign in on the same device within a day of winning, the game is saved to your account; otherwise it's deleted after a day. Your preferences (see Cookies and local storage) are saved only in your own browser.

If you create an account

We collect and store:

Your email address, used to sign you in, confirm your account and reset your password.
Your password, stored only in a securely hashed form that can't be turned back into the password.
Your display name, which is shown publicly on the leaderboards.
Google sign-in details, if you sign in with Google: an identifier Google provides for your account, plus the email address and name Google shares with us. We don't receive your Google password.
Your preferences: the tile set and background you choose.

Ranked games and leaderboards

When you play while signed in, we store:

Each game's layout, start and finish times, result and score, and the number of games you've played and won.
The moves of games that reach a leaderboard, kept as proof of the score for as long as the score stays on the leaderboard. We also keep the moves of games our checks reject, for 30 days, so we can look into any problem you report. Other games keep only their result.
Leaderboard entries: your display name, score, game time and date. Leaderboards are public, so anyone visiting the site can see them. The same goes for replay lists, which rank the best scores of players who replay a leaderboard game's deal; replays keep their moves on the same terms.

How we use your information

To run the game, your account and the leaderboards.
To check that leaderboard scores are genuine.
To send account emails (confirmation and password reset). We don't send marketing email.
To keep the site secure and working, and to fix problems.

We don't sell your personal information, and we don't share it except as described in this policy.

Advertising

The site shows ads from Google AdSense. Guests see more ads than signed-in players.

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.
You can opt out of personalized advertising by visiting Google Ads Settings. You can also opt out of some third-party vendors' use of cookies for personalized advertising at www.aboutads.info.
Visitors in the European Economic Area, the UK and Switzerland are asked for consent before personalized ads are shown.

Learn more in how Google uses information from sites that use its services.

Analytics

We use Cloudflare Web Analytics to understand how many people visit the site, which pages they view and where visitors come from (for example, a search engine or another website). It doesn't use cookies or local storage, doesn't track you across other websites, and doesn't identify you personally. We see only overall totals, such as visits per day, pages, referring sites, and browser, device and country. Learn more in Cloudflare's description of Web Analytics.

Cookies and local storage

The site itself uses only cookies it needs in order to work:

Sign-in cookies keep you signed in, and handle signing in with Google.
A security cookie protects forms, such as sign-in and registration, against forgery.
Server routing cookies (ARRAffinity), set by our hosting provider, keep your visit on the same server.

The game also saves your tile set, background, last layout and sound setting in your browser's local storage, so they're remembered next time, along with the code for a guest win waiting to be saved. This stays on your device; clearing your browser's site data removes it.

Google's advertising cookies are described under Advertising above.

Service providers

We use these providers to run the site:

Microsoft Azure hosts the website and its database, in the United States, and sends our account emails.
Cloudflare provides the site's domain name service and privacy-friendly visit statistics.
Google provides Google sign-in (if you use it) and advertising.

Like most websites, our hosting provider records technical information about requests, such as IP addresses and browser details, to keep the service running and secure.

How long we keep information

Account information is kept until you delete your account.
Stored moves are kept as described under Ranked games and leaderboards.
When you delete your account, your sign-in details, email address and preferences are deleted. Your leaderboard entries (display name, score, time and date) stay on the leaderboards, and your game history is kept without being linked to any account. If you'd like your leaderboard entries removed as well, email us at karl@kabkolor.com.

Your choices and rights

You can change your display name at any time under your account.
You can download your personal data, or delete your account, under Personal data.
You can play as a guest without creating an account.
Depending on where you live, you may have rights to access, correct, delete or move your personal information, or to object to how it's used. To make a request, email karl@kabkolor.com.

Security

The site uses HTTPS encryption, passwords are stored hashed, and access to the database is restricted. No method of transmission or storage is completely secure, but we work to protect your information.

Children

The site isn't directed at children under 13, and we don't knowingly collect personal information from them. If you believe a child has created an account, contact us and we'll delete it.

Changes to this policy

If we change this policy, we'll update it on this page and change the date at the top. Significant changes will be highlighted on the site.

Contact

KabKolor · karl@kabkolor.com