Introduction to Entropy32 Plus
A new open-source project named Entropy32 Plus is harnessing the unpredictable nature of radioactive decay to generate Bitcoin recovery phrases, specifically BIP39 seed phrases, which are essential for wallet recovery. Developed by Alexander Higgins and made available on GitHub in September 2026, this device is designed as a learning tool and emphasizes that users should not use it for significant cryptocurrency amounts until its reliability has been independently verified.
The Universe Bifurcator
The device, dubbed The Universe Bifurcator, utilizes a Geiger counter to measure decay events and translates the timing of these events into randomness, steering clear of conventional software-based entropy generation. Decay events are inherently random; thus, using their timing as a source of entropy adds a layer of security.
Technical Specifications
Connected to a GQ Electronics GMC-320S Geiger counter, the device relies on a 3.5-millimeter jack for its input. The counter detects radioactive emissions, and after capturing a pulse, an LM393 comparator converts the analog signal into a digital format for processing. This input is then relayed to an ATmega328P microcontroller, which records the timing of each decay event using precise microsecond intervals.
Higgins notes that only intervals that differ from one another are counted, while equal intervals are disregarded to maintain randomness. Those that last under 200 microseconds are filtered out as potential noise. The goal is to collect a pool of 512 bits from these interval comparisons before undergoing a transformation.
Hashing and Recovery Phrase Generation
Once enough bits have been gathered, the Entropy32 Plus firmware processes the data using the SHA-256 hashing algorithm. The first 16 bytes of the hash are used to create a 12-word recovery phrase, while a full 32 bytes yield a 24-word phrase. This hashing process helps obfuscate any detectable patterns that might arise from variables such as detector dead time or active radiation levels.
To ensure reliability, the firmware includes a startup test for the SHA-256 implementation, verifying that its results match an expected value. However, it does not assess the performance of the Geiger counter or the independence of pulse events. For now, the available information does not specify how much effective entropy is contained in each comparison.
BIP39 Standard Compliance
Described in further detail, the BIP39 standard requires that the generated phrases consist of words drawn from a predetermined list of 2,048 terms. With the system’s firmware housing a complete compilation of this word list, the program has efficiently utilized the microcontroller’s memory, leaving minimal space unallocated.
Security Features and User Interface
One crucial feature of the Entropy32 Plus is its lack of persistent storage or wireless communication capabilities, minimizing potential attack vectors. Instead, users manage the generator through a straightforward interface with two buttons and can read the generated phrases on a small OLED display. Once the words are recorded, a confirmation process erases the temporary storage of word indexes to prevent any leakage of sensitive information.
Risks and Recommendations
Despite its innovative approach, Higgins advises users about the inherent risks. The project notes that the entropy source has not yet undergone the rigorous testing outlined in NIST Special Publication 800-90B, which is vital for evaluating physical randomness sources. He encourages users to supplement this method with another source of verified entropy before committing significant funds to a wallet.
In light of previous incidents where weak entropy in wallet generation has resulted in vulnerabilities—such as documented flaws in the Coldcard device—Higgins’ Entropy32 Plus highlights the ongoing need for thorough testing in cryptocurrency tools. Current indications show ongoing development, with no finalized audit or public dataset associated with the raw decay events captured as of mid-September 2026, leaving potential users to consider their risk before utilizing this technology.
