UidLookup Precompile

Last updated: Aug 03, 2026

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The UidLookup precompile maps an EVM address to the UIDs of neurons that have associated it via the associate_evm_address extrinsic.

• Address: 0x0000000000000000000000000000000000000806
• Source code: UidLookup reference

See also: Associating an EVM Key.

Function

Function	Parameters	State mutability	Description
uidLookup(uint16 netuid, address evm_address, uint16 limit)	address	view	Allows for UID lookup when provided with EVM address.

Usage

ABI

The canonical ABI is defined in the UidLookup precompile ABI source file. If you have a local copy of the source files, you can import the ABI and contract address into your project as shown below:

import { IUIDLookupABI, IUID_LOOKUP_ADDRESS } from "./contracts/uidLookup";

Look Up Neurons Associated with an EVM Address

import { ethers } from "ethers";
import { IUIDLookupABI, IUID_LOOKUP_ADDRESS } from "./contracts/uidLookup";

const provider = new ethers.JsonRpcProvider("YOUR_RPC_URL");
const uidLookup = new ethers.Contract(
  IUID_LOOKUP_ADDRESS,
  IUIDLookupABI,
  provider,
);

const netuid = 1;
const evmAddress = "0xYourNeuronEvmAddress";
const results = await uidLookup.uidLookup(netuid, evmAddress, 10);

for (const item of results) {
  console.log(`UID ${item.uid} associated at block ${item.block_associated}`);
}