Ergo Namespace - Addresses

Author Yuriy Gagarin
Status Draft
Type Standard
Created 2023-11-02
Updated 2023-11-09
Requires CAIP-2, CAIP-10


For context, see the [CAIP-10][] specification.


A given Ergo “address” changes completely depending on the network identifier segment. Different address types in the Ergo-specific UTXO model, like the network identifier used to encode the network on which the address can be dereferenced, can only be determined by decoding the string and inspecting the initial prefix byte. This prevents unintentional transfers across Ergo blockchains.

Constructing an address:

  • Prefix byte = network identifier + address type discriminant
  • checksum = leftmost_4_bytes (blake2b256 (prefix byte || content bytes))
  • address = prefix byte || content bytes || checksum

Network type is 8-bit unsigned integer in which lower 4 bits are zeros.

Possible values:

  • Mainnet - 0 (in hex 0x00)
  • Testnet - 16 (in hex 0x10)

Address types are (semantics described below):

  • 0x01 - Pay-to-PublicKey(P2PK) address
  • 0x02 - Pay-to-Script-Hash(P2SH)
  • 0x03 - Pay-to-Script(P2S)

For an address type, we form content bytes as follows:

  • P2PK - serialized (compressed) public key
  • P2SH - first 192 bits of the Blake2b256 hash of serialized script bytes
  • P2S - serialized script One the above has been constructed in binary, it is encoded according to the Base58btc alphabet to be expressed as the address segment of a CAIP-10 string. The checksum is calculated after concatenating prefix byte to content bytes, and then postpended to form a full Ergo standard address notation.


The syntax of Ergo addresses:

caip10-like address:    namespace + ":" chainId + ":" + address
namespace:              ergo
chain Id:               32-character prefix from the hash of the genesis block 
address:                Ergo address represented as a [Base58btc][]-encoded string

Test Cases

# Namespace-wide bare public key in standard expression, without prefixes
# 0x0202f2b96aa59e6f37fc978883f78e54fd319fa37dcf971d8e69f9e9225376bcf1

# P2PK Address on Ergo Mainnet

# P2PK Address on Ergo Testnet

Copyright and related rights waived via CC0.


Please cite this document as:

Yuriy Gagarin, "namespaces/ergo-caip10: Ergo Namespace - Addresses [DRAFT]," Chain Agnostic Namespaces, ergo-caip10, November 2023 / November 2023. [Online serial]. Available: