MetaMask

For the thing that actually empties wallets — being tricked into signing something — MetaMask is among the best-defended options available. Its transaction simulation shows you what a signature will do to your balances before you approve it, and its phishing detection catches a large share of the sites built to take your funds. Those two features prevent more real losses than any amount of cryptographic purity.

The custody model is sound and ordinary: you hold a standard seed phrase, Consensys never has it, and the phrase is portable to any other wallet, which we score 9 out of 10. Nobody can freeze your funds and nobody can recover them for you.

The gap is privacy, and we score it 2 out of 10. By default your requests go through Consensys infrastructure, which means one company can associate your IP address with every address you hold and every contract you touch. That is not a theft risk. It is a profile of your entire on-chain life sitting with a single commercial party, and most users have no idea it is the default. Changing the RPC endpoint fixes it and almost nobody does.

The other real cost is the swap fee. Using the in-wallet swap adds a charge on top of whatever route it selects, which is how a free wallet is paid for. We score that 3 out of 10. Swapping on the exchange itself and bringing the result back is usually cheaper.

This is the most persistent piece of folklore in crypto wallets and it is five years stale. In 2020 MetaMask moved to a proprietary Consensys licence that forbids commercial use beyond a defined user threshold. You can read the code. You cannot freely use it, fork it into a product, or treat it as community-owned software.

Why it matters is not ideology. "Open source" in a wallet is a claim about verifiability — that anyone can check the thing handling your keys does what it says. A readable-but-restricted licence preserves most of that inspection value, so the practical security argument survives largely intact, and the governance argument does not: this is a company’s product, changed on the company’s terms.

Where it bites is the ecosystem. Forks and derivatives that would otherwise exist cannot be shipped commercially, which concentrates the most-used wallet in crypto in the hands of one firm. Given the default RPC already routes through that same firm’s infrastructure, the concentration is the thing to notice rather than the licence text.

Our transparency score is still 8 out of 10, because on audits and disclosure Consensys does considerably better than most. Not open source and not opaque are different accusations, and only the first one is true here.