Validates a BIP39 recovery phrase, finds the wrong word, and suggests the fix. This file runs entirely on your machine; the whole point of downloading it is to disconnect from the internet before you use it.
What this needs, and what it doesn't. This tool has to see the phrase to check it, there's no way around that. Here's what it promises instead: it never transmits anything, anywhere (zero network requests, check your browser's network tab), it never stores anything (no cookies, no localStorage, nothing written to disk), and it never asks for more than the phrase itself. No passphrase, and it never derives keys, addresses, or balances.
Given that, be deliberate about where you type a full phrase. Safest: you're already there, this is the offline copy, disconnect from the internet, run it, and close the browser before reconnecting. Also fine on the live page: type only the single word you're unsure about, not the whole phrase.
Nothing typed here is uploaded or saved. State lives only in this tab and disappears when you close it.