How MetaMask backs up wallet data with 3Box

3Box Partner Series

Michael Sena
Oct 29 · 3 min read

Decentralized Wallet Data Backup and Sync

We’re excited to announce that MetaMask has begun offering a new feature that allows users to back up their wallet data to 3Box. Now, instead of keeping MetaMask wallet data such as account information, settings, and contact lists in browser localStorage where it remains siloed, MetaMask users can now securely store this information in 3Box where it is liberated and conveniently available wherever users access their Ethereum account.

Currently MetaMask is rolling out optional 3Box backup to its users on browser extension v7.3.0 and later. To enable 3Box, navigate to Settings > Advanced, and then toggle on 3Box Sync. This should be available to you today!

Looking ahead, if the rollout goes smoothly (we expect it should) MetaMask will very soon enable 3Box backup by default and provide users the option to turn it off.

Don’t have MetaMask? Download the Chrome extension.

Why did MetaMask choose 3Box for backup?

Previously, MetaMask only saved user extension data to browser localStorage. This storage model was decentralized but offered a poor user experience. You may have noticed this when your MetaMask extensions on different browsers (such as Chrome and Firefox) had different data, or when you got a new computer and noticed none of your old MetaMask data was available on your new machine.

By instead saving this data to 3Box, it’s liberated from the confines and restrictions of browser localStorage and is made available to users wherever they access web3 with their Ethereum account. Now users can experience an automatic, seamless data sync experience between all of their MetaMask extensions and never have to deal with out-of-sync extension data again. In the future, this data will also be synced with the MetaMask mobile wallet, for a completely seamless web3 wallet experience.

Beyond the simple user experience benefits of automatic data sync, 3Box also improves the security model of MetaMask by making user data more persistent. Historically, if a user lost their device or deleted their browser, their MetaMask data would have also been lost. Now, data lives outside the confines of the browser and is more resilient and available.

What’s next for 3Box and MetaMask?

This is just the start of a fruitful partnership between MetaMask and 3Box. During Devcon 5, MetaMask introduced a developer beta of their new web3 plugin system, MetaMask Snaps, which now features 3Box as a premier identity and user data plugin. Behind the scenes, this system will allow MetaMask to integrate directly with the 3Box IdentityWallet SDK, which exposes the 3ID data protocol to app developers building with MetaMask. We will be announcing more about this system as we approach the official launch of MetaMask plugins. Stay tuned!

Want to integrate 3Box into your wallet or app?

We’re always online and available to chat in Discord if you have any questions about the MetaMask integration or anything else. #BuildBetter 3️⃣


APIs for decentralized profiles, storage, and messaging. Learn more at

Michael Sena

Written by

Helping developers #BuildBetter apps @3box. Happy contributor to the decentralized web. Fair data advocate.



APIs for decentralized profiles, storage, and messaging. Learn more at

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