How Offline Minesweeper works
The board generator, timer, reveal rules and saved progress run in your browser. The first connected visit installs a service worker and stores a credential-free copy of this game shell. When the network is unavailable, the browser can open that saved shell instead of requesting a fresh page from the server. A board already in progress is stored locally on the same browser and difficulty.
Offline mode is designed for travel, unreliable connections and private practice. It does not submit a result to a ranked leaderboard. A disconnected result cannot receive the same server-side session checks as a connected ranked game, so keeping the two result types separate protects the meaning of the public rankings.
Start and control a local board
- Choose Beginner, Intermediate or Expert before starting a new board.
- Select Reveal to open cells or Flag before tapping cells that you believe contain mines.
- Use Copy challenge link to share the current difficulty and seed. The recipient gets the same generated field, but their progress is separate.
- Start a new board whenever you want a new seed. Changing difficulty also creates a board with that preset's standard dimensions and mine count.
Install Minesweeper.now as an app
On a supported desktop or Android browser, select Install app when the button appears. Some browsers place the same command in the address bar or main browser menu. On iPhone or iPad, open this page in Safari, use the Share menu, and choose Add to Home Screen. Launch the installed icon once while connected so the current game assets can be stored.
The install button is controlled by the browser and may not appear if the app is already installed, private browsing is active, storage is blocked, or the browser does not expose web-app installation. Installation is optional: the normal browser page can still work offline after a successful connected visit.
What is saved on this device
The active local board, seed, revealed cells, flags and elapsed state are kept in browser storage. They are not synchronized to another device or browser profile. Clearing site data, using an automatic storage-cleanup feature, or uninstalling the web app can remove that local progress. A copied seed link recreates the field, but it does not carry your revealed cells, timer or flags.
What still needs an internet connection
Account sign-in, ranked submissions, public profiles, purchases, multiplayer, tournaments and live leaderboards require a connection. The installed shell can display the local game without those systems, but it cannot safely invent or queue competitive records while the server is unreachable.
Offline play questions
Why does the page need to be opened once while connected?
The browser must download the page, styles, game engine and service worker before it has anything to use offline. Visit again after a major site update if you want the newest cached version.
Does the same seed always create the same board?
Yes, when the difficulty and generation rules are the same. The challenge URL includes the difficulty and seed so another player can reproduce the field. It remains an unranked local challenge.
Why did my saved board disappear?
The most common causes are cleared cookies and site data, private-browsing cleanup, browser storage pressure, or switching to another browser profile. Local storage is convenient but is not a permanent cloud backup.
For connected competition, open a ranked Beginner board. To author a fixed mine layout rather than a generated seed, use the Minesweeper puzzle creator.