About MetaMask
MetaMask is the best-known browser wallet, made by Consensys, and its Chrome listing shows about 12 million users. It is self-custodial, so you hold the keys, and it signs transactions for the sites you connect to. The Chrome listing names Ethereum, Bitcoin, Solana and BNB Chain among its supported networks.
It has the broadest browser coverage in this list, with Chrome, Firefox and Edge listings, and its download page also names Brave and Opera. The Chrome version runs on Manifest V3. The code is public on GitHub, and MetaMask's security page lists audits including Least Authority's review of the extension's seed phrase implementation in 2022, plus a HackerOne bug bounty. In 2022 Halborn disclosed the "Demonic" flaw, which affected several extension wallets including MetaMask; fixes were released and the wallet providers reported no evidence it was exploited.
Two warnings. The source is viewable, but the licence is a custom Consensys one that bars commercial reuse, so it is not open source in the strict sense. The extension also needs permission to read and write every web page, as its listing explains. Fake wallet extensions are common, so use the link from MetaMask's official site. Choose it when compatibility matters most.
Pros and cons
- Listings in Chrome, Firefox and Edge
- Source code is public on GitHub
- Public audits and a HackerOne bug bounty
- Frequent updates and 24/7 human support listed
- Licence restricts commercial reuse, so not strictly open source
- Needs access to every web page
- Fake MetaMask copies are a known scam risk
Permissions
It asks for permission to read and write any web page so it can connect to apps, plus storage, notifications, cookies and web request access. The Chrome listing explains the all-pages access and links to the source code.
