I built a BIP-39 seed phrase scanner that reads raw disk sectors - and just open-sourced the engine

M Media — Fri, 03 Apr 2026 18:51:18 +0000

A friend of mine lost his wallet somewhere in an ocean of working and non-working drives. I built this initially to help him rule out, at the very least, where it wasn't.

The tool reads every raw byte of a physical disk at the sector level - not just the file system. It runs a sliding-window BIP-39 sequence extractor across every 1MB block and validates every candidate phrase against the full BIP-39 checksum spec. False-positive rate for random word sequences: 1 in 256. When it returns a match, it is cryptographically verified, not just a word count.

Zero network calls. Zero telemetry. Your words never leave the machine. You can verify that yourself with grep in about 30 seconds.

The commercial tool is a Windows app, but the core engine - LowLevelScanner, BIP39Checksum, Bip39Sequence - is now MIT on GitHub. Real code, not a demo. Same routines that run in the product.

Repo: https://github.com/mmediasoftwarelab/BIP39RecoveryTool-public

Published for transparency - if you're running recovery software on a machine that might have held a seed phrase, you should be able to read every line of code that touches your data.

Happy to answer questions about the implementation.

DEV Community: M Media

I built a BIP-39 seed phrase scanner that reads raw disk sectors - and just open-sourced the engine