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Cryptographic entropy

Unpredictability available to generate secret keys; it is measured by the attacker’s remaining uncertainty, not by how random output looks.

Unpredictability available to generate secret keys; it is measured by the attacker’s remaining uncertainty, not by how random output looks.

Cryptographic entropy is best understood as part of a system rather than as an isolated definition. Its related coordinates show the mechanisms, incentives and historical records that give the term practical meaning.

Cryptographic entropy should be evaluated against a concrete threat model: what is protected, from whom, for how long and at what operational cost. A design may remove one dependency while introducing another, so custody, privacy and verification must be judged as a complete system.

Understanding Cryptographic entropy helps distinguish a verifiable Bitcoin mechanism or historical record from slogans, products and market narratives.

For the clearest picture, read this entry together with Bits of entropy, Random-number generator, Cryptographically secure PRNG, Wallet seed generation. The reverse links also lead from Dice-roll entropy, Bits of entropy, Random-number generator, Cryptographically secure PRNG.

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Linked to related atlas coordinates

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Grounded in source data

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Explains function and trade-offs

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Part of the open Bitcoin knowledge graph

DOC · 001NIST SP 800-90A Rev. 1 — Random Number GenerationSpecification
Reviewed 1 August 2026Source-first · No investment advice