BIP-85 turns a single master seed into a generator for unlimited, unrelated child seeds — new mnemonics, passwords, and keys that look like they came from nowhere, but can always be regenerated from the one thing you actually back up.
One root, five independent, unlinkable outputs — each reproducible only if you know the master seed AND the exact index used
Normal wallets derive many addresses from one seed (BIP32/BIP44) — but those addresses are all visibly part of the same tree. BIP-85 goes a level further: it uses your master seed to produce entirely new, standalone secrets that have no visible mathematical link to each other or to the parent, even though they all come from the same root.
You only need to physically secure your master seed. Every child can be regenerated on demand from it.
Someone holding one derived seed can't trace it back to the master, or connect it to any other child.
Mnemonics, WIF keys, raw hex entropy, even passwords — the "application" number decides the format.
Every BIP-85 output is generated using a fixed path structure. The wallet runs your master key through HMAC-SHA512 following this path, and the result becomes the entropy for the new secret.
m / 83696968' / app' / index / ... / child_index'
The same seed already sitting in your hardware or software wallet — no new setup required to begin.
Decide what you want out: a 12-word mnemonic, a 24-word mnemonic, a private key, a password. Each type has its own application number, plus an index (#0, #1, #2…) to keep them distinct.
Your master key plus that exact path is hashed. The output bytes become the entropy for the new secret.
Those bytes are formatted into a valid BIP39 mnemonic (or WIF key, or password) — one that's indistinguishable from a freshly, randomly generated one.
Import the resulting phrase into any wallet software. It behaves completely independently from this point on.
Generate a distinct wallet for savings vs. daily spending, without managing two unrelated backup phrases.
Create a brand-new, independent seed to give to a family member — it never reveals anything about your own master seed.
Spin up disposable "test" wallets for trying new software, safely separated from real funds.
Derive deterministic, high-entropy passwords for other accounts, from the same master seed you already secure carefully.
Generate multiple independent keys for a multisig setup from one root, instead of juggling several separate seeds.
A walkthrough covering the same ground in video form.
If you forget which application number and index you used for a child seed, you cannot regenerate it — even with the master seed in hand. Keep a record of what you derived.
Anyone who gets your master seed AND your index list can regenerate every child you've ever made. Protecting the master matters more than ever.
BIP-85 requires explicit support in your hardware or software wallet. Verify compatibility before relying on it for real funds.
This page is provided for general educational purposes only and does not constitute financial, legal, security, or technical advice. Bitcoin and cryptocurrency self-custody carry real risk of permanent, irreversible loss of funds through user error, software bugs, lost seed phrases, lost derivation indexes, hardware failure, or theft.
I am not responsible for any loss of Bitcoin or other cryptocurrency resulting from the use, misuse, or misunderstanding of the information on this page. Always test with small amounts, verify your backups, and consult qualified professionals before managing significant funds.