Address Prefix

Overview

Address prefixes provide context before the payload of an address. In Bech32-style addresses, the human-readable part can indicate the network, such as `bc` for Bitcoin mainnet. Other networks use hexadecimal markers, version bytes encoded into Base58 strings, or readable labels.

A prefix improves usability but should not be treated as complete validation. Some networks share similar visual formats, and a prefix may distinguish only the network family rather than the exact asset or destination type. A valid prefix also cannot confirm ownership or whether a destination requires a memo or tag.

Software should parse addresses using protocol-aware libraries. Prefix checks are useful as an early validation step, but the complete payload, checksum, version, length, and network rules must also be verified.

For merchants, a clear prefix can help detect obvious wrong-network entries. However, users should still follow the network shown by the payment request, because two networks may support similar-looking addresses without sharing state.

Human-readable prefixes are especially helpful when the same encoding supports several environments. Bitcoin Bech32 uses `bc` for mainnet and different prefixes for test networks. Other ecosystems use prefixes to indicate chain families, account types, or address versions.

A prefix should not be interpreted as an asset symbol unless the protocol defines it that way. Tokens on the same network usually share the network’s account format rather than receiving separate address prefixes. Attackers can also create text that begins with a familiar prefix but fails the full checksum. Reliable software therefore decodes the complete address and rejects unsupported combinations instead of checking only the leading characters.