mnemonicToEntropy
Extracts the raw entropy bytes from a BIP-39 mnemonic phrase.
This is the inverse of generateMnemonic — given the words, it returns the bit pattern they encode. Used by wallet storage to persist entropy (smaller than the phrase, reproducible to the phrase on demand).
12 words → 16 bytes
15 words → 20 bytes
18 words → 24 bytes
21 words → 28 bytes
24 words → 32 bytes
Return
The raw entropy bytes
Parameters
mnemonic
The BIP-39 mnemonic phrase
Throws
if mnemonic is invalid