Knowledge base
Seed Standards Compared: BIP-39, Electrum, SLIP-39 and Others
Not every recovery phrase is a BIP-39 phrase. Electrum, SLIP-39 and Monero each have their own seed system - and compatibility between them is limited.
Short answer
Recovery phrases are not interchangeable: BIP39, Electrum and SLIP-39 seeds restore different wallets. The standard the phrase was created with decides compatibility — a phrase that works in one wallet family can fail another, even when the words look the same.
Recovery phrases look similar but are not interchangeable. Whether a seed restores a wallet depends on the standard it was created with, and mixing standards is one of the hidden causes of failed restores.
BIP39 (most hardware and software wallets)
- 12, 15, 18, 21 or 24 words from the fixed BIP39 word list (2,048 words)
- The last word contains a checksum: the checksum detects some errors, not all. A changed BIP-39 phrase can still pass validation and produce a different wallet.
- An optional BIP39 passphrase (25th word) changes the derived wallet entirely
- Used by Ledger, Trezor, MetaMask, most mobile wallets and most modern desktop wallets
- BIP-39 compatibility alone is not enough: the wallet must also support the original network, derivation paths, account and address types, and any passphrase used.
Electrum seeds
- Older Electrum seeds (before version 2.0) use a fixed historical word list to encode the seed as words and decode the words back into the seed. They do not use the HMAC-SHA512 version-hash system introduced in Electrum 2.0.
- Newer Electrum seeds: 12-24 words, validated by Electrum's own version hash — a prefix of an HMAC-SHA512 of the phrase, not a separate word
- Not BIP39: an Electrum seed will not restore a BIP39 wallet and vice versa
- Electrum also uses its own derivation paths (legacy / SegWit branches) on top of the seed
SLIP39 (Shamir backup)
- Splits a seed into shares; a threshold of complete shares restores the wallet (for example 2 of 3)
- Shares are 20 or 33 words from the SLIP39 word list
- Used by Trezor (Shamir backup) and some other hardware wallets
- The shares reconstruct the wallet's underlying master seed — the value every key is derived from — not a BIP39 phrase
- SLIP39 replaces BIP39 rather than extending it, and the two are not compatible: existing shares cannot be converted back into a 12 or 24-word BIP39 phrase
- If you hold Shamir shares, keep them in SLIP39 form and restore them in software that implements SLIP39: a 20 or 33-word share is not a phrase a BIP39 wallet can take
Monero seeds
- 25 words encoding the private spend key and private view key
- Has its own checksum and its own word list
- Not BIP39; Monero seeds restore only Monero wallets (and compatible software)
Legacy and non-standard seeds
- MultiBit Classic, early Bitcoin Core and other pre-HD wallets do not use a seed at all: they used wallet files and keypools
- Brain wallets are passwords turned directly into keys, not seeds
- Any custom '12 or 24 words' that fail the BIP39 checksum may still be valid under another standard: that is a signal, not a dead end
What this means for recovery
- Before judging a seed invalid, identify the standard: the word count, whether the phrase carries Electrum's version hash, and whether the software is BIP39-based
- An 'invalid seed' error in one wallet does not mean the seed is unusable: it may belong to another standard
- Recovery of a partial or wrong seed depends on the standard's checksum structure, which is what makes bounded searches possible
Still locked out?
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