This started as a fun JS experiment for myself, exploring how seed phrases are built from entropy. After positive feedback from friends, I turned it into a full guide to wallet recovery phrases - covering entropy, checksums, SHA-256, and how it connects to HD wallets (in a hopefully accessible way).
It’s fully interactive - flip bits, see your mnemonic change. I hope it offers an intuitive way to understand what’s going on under the hood.
Feedback and suggestions very welcome.