Blockchain.com · BTC

Recover a Blockchain.com wallet.

Blockchain.com (formerly Blockchain.info) is one of the oldest web wallets. The wallet is a JSON payload encrypted under a password you set.

Why people get locked out

People get locked out when they forget that password but still have their wallet backup or identifier.

Can we recover it?

Yes. Blockchain.com is one of the formats that reduces to a check-only extract, so the fleet can test passwords against it safely — finding the password never exposes a key that holds funds. GPU-friendly — the password math is fast and repetitive. You pay 15% only if we recover it, and nothing if we don't.

Under the hood

The Blockchain.com extract, in detail.

Exactly what the fleet receives for this format — and why finding the password still can't move the funds.

Anatomy of the extract

What leaves your machine — and what never does

For a Blockchain.com wallet, this is the entire check-only extract the fleet receives. It can test a password, but it can never be turned back into a key that spends.

GPU $blockchainx$
in the extract
  • the first 16-byte ciphertext block of the encrypted wallet JSON
  • the 16-byte IV, which also acts as the PBKDF2 salt
  • the stored iteration count, or the v0 default-10 sentinel
  • a small format marker and CRC wrapper
stays on your device
  • the seed and private keys — in the later ciphertext blocks, never sent
  • your wallet GUID, addresses, and balances
how a guess is checked

A correct password decrypts the block to recognizable Blockchain.com wallet JSON field names such as "guid", "sharedKey", or "keys". That confirms the guess; the keys sit in blocks that were never transmitted.

verifier Blockchain.com JSON fields such as "guid", "sharedKey", or "keys"
example extract
illustrative · synthetic
$blockchainx$<base64("bk:" | first-block | iv | iter32 | crc32)>

Illustrative and synthetic — placeholder bytes in the shape Distribrute uses for check-only Blockchain.com extracts.

on the wire

43 decoded bytes — a format marker, the first ciphertext block, the IV, the iteration count, and a CRC wrapper.

password math (KDF)
PBKDF2-HMAC-SHA1

PBKDF2-SHA1 over the password, using the wallet's IV as salt; the iteration count is stored in the wallet (v2 and later).

how a guess is recognized
Blockchain.com JSON fields such as "guid", "sharedKey", or "keys"

A correct password decrypts the block to recognizable Blockchain.com wallet JSON field names such as "guid", "sharedKey", or "keys". That confirms the guess; the keys sit in blocks that were never transmitted.

extract format
$blockchainx$

An open, published format. The agent checks every job matches it before running — so a real wallet can't be disguised as an extract.

See the full security model, or how a recovery works end to end.