A Complete Guide to Registering an Onion Domain

Registering an onion domain is essential for anyone aiming to host a hidden service on the Tor network, ensuring anonymity and privacy both for the operator and users. This article explores the onion domain registration process, the tools involved, and best practices to securely establish your hidden website, offering clear and thorough guidance.

The Process of Registering an Onion Domain

An onion domain, according to Wikipedia, refers to a special-use top-level domain suffix, .onion, designating an anonymous hidden service reachable only through the Tor network. Unlike regular domains managed by organizations like ICANN, .onion addresses are self-generated and cryptographically bound to the Tor service hosting them. To create such an address, the process begins with configuring a Tor hidden service, which involves careful cryptographic procedures to ensure both uniqueness and anonymity.

The most current and secure method involves generating a v3 .onion address. The v3 address format, now the standard since 2021, replaces older v2 addresses due to its stronger cryptography and larger key size. V3 utilizes ED25519 key pairs, providing enhanced security over the RSA1024 keys used in v2. Generation of the onion address starts with the Tor software itself. On most platforms, this means installing Tor and editing the torrc configuration file. Within torrc, you specify HiddenServiceDir to define the location for service keys and HiddenServicePort to map external ports to your service.

After configuring torrc and starting the Tor service, a new key pair is created automatically in the specified directory. The public key, alongside an encoded checksum and version data, forms the .onion address. Advanced users can employ the tor –keygen command to manually generate key pairs, particularly useful for vanity addresses. Always restrict permissions on your keys, and never share private keys.

Privacy is paramount. Always run Tor on trusted, isolated machines and keep your hidden service offline from unnecessary networks. After generating your address, only publicize the .onion address itself—never reveal backend details or expose your private keys. To publish your service, share the .onion address through secure, anonymous channels and monitor your logs for unusual access patterns. Remember, regular key rotation is a best practice for ongoing security, and storing your private keys securely is fundamental to maintaining your hidden service’s integrity.

Conclusions

Registering an onion domain is a critical step for launching private and anonymous services on the Tor network. By understanding the technical requirements and following best security practices, you can ensure both your site’s effectiveness and user privacy. With proper planning, your onion service can thrive in the unique environment of the dark web while maintaining strong protection against exposure.