Check whether a word belongs to the official BIP39 wordlist and catch typos. Full-phrase mode exists, but it sits behind a warning: typing your seed phrase into any web page is exactly the habit scams exploit.
CryptoLV will never ask for your seed phrase
No legitimate support desk, airdrop or verification process needs your recovery phrase. Anyone asking for it is stealing from you. This page works offline: use word mode whenever you can.
The wordlist has 2048 words and the first four letters uniquely identify each one. Almost every real problem with a paper backup is a single misread word.
BIP-39 defines how random entropy becomes a memorable word list. The entropy is split into eleven-bit groups and each group indexes one of the 2048 words in the wordlist. A few checksum bits derived from the SHA-256 of the entropy are appended: one for every 32 bits. That is why a 12-word phrase encodes 128 bits of entropy plus 4 of checksum, and a 24-word phrase encodes 256 plus 8.
That checksum is what makes a validator useful. Swap one word for another wordlist word and the phrase still consists of valid words, but the checksum stops matching and any wallet will reject it. The tool tells you exactly which of the two things failed: a word that is not in the wordlist, a word count that is not permitted, or a checksum that does not add up.
The wordlist is built to tolerate human error. Words were chosen so that the first four letters uniquely identify each entry, and confusingly similar pairs were avoided. That is why word mode, with edit-distance suggestions, solves most real cases: what you usually have is one misspelled or misread word from a paper backup, not an entirely corrupted phrase.
One warning that comes ahead of the functionality: this tool never derives a seed, a private key or an address from what you type, and it makes no network requests. But the habit of typing a seed phrase into a web page is the vector for wallet-recovery scams, and a page that looks identical to this one may be sending every keystroke to a server. If you must validate a complete phrase, do it with the device disconnected from the internet, or better, by restoring into a trusted wallet in an offline environment. CryptoLV will never ask you for your seed phrase through any other channel.
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