AirWallet AirWallet Offline in a web page
airwallet.tech/offline turns a spare phone or computer into AirWallet's offline signer from a web page: install it, turn the internet off for good, then make wallets. Backups are checked before a wallet can receive.
airwallet.tech/offline is the offline half of AirWallet as a web app. It has the same screens as the AirWallet Offline app: wallets, signing, the codes for other wallet apps, vanity requests. It runs on any device with a recent browser, an old iPhone or a Chromebook included, with nothing to install from an app store.
The rule that makes it safe: install it while the device is online, then turn that device's internet off for good, and only then create wallets.
Set it up
- On the device you'll keep offline, open airwallet.tech/offline/app while it still has internet.
- Add it to the home screen. iPhone and iPad: in Safari, Share → Add to Home Screen. Android: in Chrome, ⋮ → Install app. Mac, Windows, Linux, ChromeOS: in Chrome or Edge, the install icon at the right of the address bar (Safari on a Mac: File → Add to Dock).
- Open it once from the new icon and wait for "Ready to work offline". Everything it needs is then kept on the device.
- Turn the internet off for good: airplane mode, Wi-Fi and Bluetooth off, saved Wi-Fi networks forgotten.
- Create your wallets.
While the device is still online, the app says so at the top of the screen, and making a wallet asks once more first.
Backups come first
A browser can delete what it keeps: clearing a site's data, a storage cleanup, a reset. So each wallet made here is backed up before it can receive anything:
- After you write the words down, the app asks for three of them, at random places. A single private key asks for its last 6 characters.
- Until then, the wallet shows "Not backed up yet", and Receive, Show to my online wallet and Use with another app take you to the backup instead.
- Imported words count as backed up already: they were written somewhere to be typed in.
The app also asks the browser to keep its storage. An installed app usually gets that.
Restore
Your coins are on their blockchains, not in the browser. To get a wallet back, type its words into AirWallet on any device (+ → Import), or into another wallet app such as Sparrow, MetaMask, Phantom or Cake Wallet.
For everything at once, names included, save a backup file too: Settings → Back up all keys → Save as a file. Move the file to a USB stick or SD card. On any copy of AirWallet, Import → the file brings it all back.
Where it runs
| Device | Browser | Install with |
|---|---|---|
| iPhone, iPad | Safari, iOS 16.4 or newer | Share → Add to Home Screen |
| Android | Chrome, Edge, Samsung Internet | ⋮ → Install app |
| Mac | Chrome, Edge, Safari 17 or newer | Install icon; Safari: File → Add to Dock |
| Windows, Linux, ChromeOS | Chrome, Edge | Install icon in the address bar |
On an iPhone, the installed app keeps its own storage, apart from Safari's. Firefox runs it in a tab but can't install it on a computer. Monero and Zcash need a browser from 2021 or later; the other coins run on older ones too.
How it stays offline
The page never connects to anything. Its host part refuses every network request, and its Content-Security-Policy says connect-src 'none', so the browser itself refuses any connection the page tries. The site serves the same policy as a header, and to the Monero and Zcash engines' workers too.
A service worker keeps the app and its engines on the device and serves them from there, with or without a connection. It never replaces them by itself. A new version installs only when you press Update this device's copy on airwallet.tech/offline. An offline signer doesn't need updates: newer online copies keep making codes older ones read (see Updates, downloads and outside code).
The risks
- The website hands you the code. Whoever controls airwallet.tech when you install could hand you different code. Once the device is offline for good, nobody can change it.
- The browser keeps your wallets. That's why backups are checked first.
- A browser is less locked down than the apps. The AirWallet Offline app for Android has no network permission at all. This page relies on the device's internet being off and on its own policy. Use a browser without extensions on that device: extensions can read pages.
- Wallets aren't encrypted unless you lock them. Settings → App lock seals them with a password.
The most locked-down choice is still the AirWallet Offline app. Its online half can be the AirWallet app or AirWallet Online, any version of either.