Privacy Policy

Last updated: 6 November 2026

This policy explains what onlinemahjong.net collects and what it does with it. The site is run by a private individual, not a company. The short version: there are no accounts, the game itself keeps nothing about you, and what does leave your device goes to the analytics and advertising providers described below.

What we collect

Nothing you type or click is stored. There is no sign up, no login, and no profile. The puzzle you are playing lives in the address bar as a five character ID, which means the board can be shared or reopened by anyone with that link, and nothing about your game is kept on our side.

The game itself sets no cookies and writes nothing to your browser storage. Close the tab and no trace of your game is left behind. The cookies on the site come from Google Analytics and Google AdSense, both described below.

Analytics

We use Vercel Analytics to count page views and measure how quickly pages load. It records things like which page was viewed, the referring site, and rough device and country information. It does not set cookies, does not follow you to other sites, and does not build a profile of you. Vercel describes how it handles this data in its privacy policy.

We also use Google Analytics (GA4) to understand how people find the site and which pages they use. It sets cookies in your browser, such as _ga, and collects data including the pages you visit, your device and browser type, and an approximate location worked out from your IP address. Google describes how it handles this data in its privacy policy. You can opt out across all sites with the Google Analytics opt out add on, or by blocking cookies for this site in your browser.

Neither of these two measurement tools is given anything you do inside the game, and neither decides which ads you see; advertising is covered in its own section below. Because their data is not linked to a name or an account, we cannot look up or delete the measurements belonging to any one visitor.

Hosting

The site is hosted on Vercel. As part of serving pages, Vercel processes technical request data such as IP addresses and server logs, for performance and to block abuse. That is handled under Vercel's own policy, linked above.

Advertising

This site shows ads through Google AdSense, which is our only advertising partner. As a third party vendor, Google uses cookies to serve ads based on your visits to this and other sites, and may collect data such as your IP address, browser type, the pages you visit and how long you spend on them. That data is handled under Google's privacy policy.

You can turn off personalised advertising in Google's Ad Settings, or opt out of third party vendor cookies at aboutads.info. Turning personalisation off does not remove the ads, it only makes them less relevant to you.

If you are in the European Economic Area, the United Kingdom or Switzerland, Google's consent message asks for your choices before personalised ads or advertising cookies are used, and you can change those choices later from the same message.

Selling and sharing data

We do not sell your data. Nothing personal is collected by the game, so there is nothing of that kind to sell. The data described above is shared with Google in its role as our analytics and advertising provider, and with nobody else.

Deleting your data

There is no account to delete and no game history held on our servers. To clear what the analytics and advertising providers have stored in your browser, clear this site's data in your browser settings. Because their measurements are not linked to a name or an account, we cannot look up or delete the records belonging to any one visitor.

Children

The site is suitable for all ages and does not knowingly collect personal information from anyone, including children. Ads shown here are not personalised for anyone Google identifies as a child.

Changes

This policy may be updated from time to time. The date at the top shows when it last changed, and continuing to use the site means you accept the current version.

Contact

Questions about this policy can go to hi@skyroth.com.