Crypto-anarchy, crypto-anarchism, cyberanarchy or cyberanarchism is a political ideology focusing on the protection of privacy, political freedom, and economic freedom, the adherents of which use cryptographic software for confidentiality and security while sending and receiving information over computer networks. In his 1988 "Crypto Anarchist Manifesto", Timothy C. May introduced the basic principles of crypto-anarchism, encrypted exchanges ensuring total anonymity, total freedom of speech, and total freedom to trade. In 1992, he read the text at the founding meeting of the cypherpunk movement.

The prefix "crypto-" originates from the Ancient Greek word κρυπτός kruptós, meaning "hidden" or "secret". This differs from its use in terms like 'crypto-fascist' or 'crypto-Jew' where it signifies that an identity is concealed from the world; rather, many crypto-anarchists are open about their anarchism and promotion of tools based in cryptology.

One motive of crypto-anarchists is to defend against surveillance of computer networks communication. Crypto-anarchists try to protect against government mass surveillance, such as PRISM, ECHELON, Tempora, telecommunications data retention, the NSA warrantless surveillance controversy, Room 641A, the FRA and so on. Crypto-anarchists consider the development and use of cryptography to be the main defense against such problems.

A 2022 study examined whether crypto-anarchism can be a useful tool in addressing socio-political issues. Their findings revealed that crypto-anarchism does not have a significant influence on actual politics, but studying it can be useful for creating political movements geared toward Internet users.

Bitcoin is a currency generated and secured by peer-to-peer networked devices that maintain a communal record of all transactions within the system that can be used in a crypto-anarchic context. Adrian Chen, writing for The New York Times, says the idea behind bitcoin can be traced to The Crypto Anarchist Manifesto. Silk Road was an example of an illegal drug market on which bitcoin was the only accepted currency.

Assassination Market was a Tor-based darknet market operated by a self-described crypto-anarchist going by the pseudonym Kuwabatake Sanjuro.

In "The Cyphernomicon", Timothy C. May suggests that crypto-anarchism qualifies as a form of anarcho-capitalism:

What emerges from this is unclear, but I think it will be a form of anarcho-capitalist market system I call "crypto-anarchy."