Experiments / Lab 01 04 Aug 2026

When 128 bits
are only 41.3

A valid mnemonic can look perfectly random while belonging to a tiny family of possible wallets. This lab makes that failure visible—and searchable.

Research and lab by Daniel Merino Security engineering · 12 min read

The surface of a cryptographic system can be impeccable: a 12-word BIP39 mnemonic, a valid checksum, a standard derivation path, and output that passes every casual visual test. None of those properties tell you how many starting states could have produced it.

Entropy Lab 01 uses a fixed, deliberately unsafe testnet fixture. Its hidden state is assembled from a simulated clock, a small device identifier suffix, and a call counter. A deterministic generator expands that state, SHA-256 makes the bytes look uniform, and normal Bitcoin standards turn the result into a fully valid wallet.

The entropy funnel

Evidence removes uncertainty.

Each observation narrows the plausible state family. Some are facts; some are search-order heuristics.

Invented weak construction2.72 trillion41.3 bits

Four-day pre-funding window362 billion38.4 bits

Minute-resolution clock3.02 billion31.5 bits

Four UID bits remain737,28019.5 bits

Fresh boot fixes call state46,08015.5 bits

Laboratory numbers are invented and deliberately bounded. The live search never accepts arbitrary wallet data.

The address becomes an oracle

A public address does not weaken a securely generated private key. But when the generator is predictable, the address gives an attacker an exact offline test: rebuild a candidate state, derive its wallet, and compare. There is no need to judge whether a guess “looks right.”

The decisive question is not “do the words look random?” It is “what generated this seed, when, and with what independent entropy?”

Why make it interactive?

Candidate counts are abstract. The lab turns them into a sequence you can operate: generate the safe specimen, apply evidence, run a real BIP39/BIP32/BIP84 testnet derivation across the bounded region, and watch the matching state reappear.

Enter Lab 01

See the collapse for yourself.

Start with the guided deck, or go directly to the interactive instrument.

01 / Interactive

Launch Entropy Lab

Generate the fixed testnet specimen, apply constraints, and search the final candidate space.

Open the lab ↗ 02 / Guided

View the presentation

Nineteen slides covering the failure model, incident lessons, search economics, and response.

Open the deck →

Safety boundary Fixed testnet fixtureNo wallet inputsNo chain queriesNo real funds