subnetInfo_getLockCost - Bittensor

Example code for the subnetInfo_getLockCost JSON-RPC method. Complete guide on how to use subnetInfo_getLockCost JSON-RPC in GetBlock Web3 documentation.

Returns the current TAO lock cost required to register a new subnet. This cost increases over time and resets after a successful registration — used as the economic gate for subnet creation.

Bittensor-specific custom RPC method. This method is implemented by the Subtensor runtime and is not part of the standard Substrate JSON-RPC surface. Call against a GetBlock endpoint configured for the Substrate interface. The Bittensor Python SDK provides typed wrappers; standard Polkadot.js and substrateinterface require the raw RPC interface (see SDK Integration tabs below).

Parameters

Parameter	Type	Required	Description
blockHash	string	No	Block hash to query at

Request Example

cURL

curl --location --request POST 'https://go.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "subnetInfo_getLockCost",
    "params": [],
    "id": "getblock.io"
}'

JavaScript (Axios)

import axios from 'axios';

const data = JSON.stringify({
    "jsonrpc": "2.0",
    "method": "subnetInfo_getLockCost",
    "params": [],
    "id": "getblock.io"
});

const config = {
    method: 'post',
    url: 'https://go.getblock.io/<ACCESS-TOKEN>/',
    headers: {
        'Content-Type': 'application/json'
    },
    data: data
};

axios(config)
    .then(response => console.log(JSON.stringify(response.data, null, 2)))
    .catch(error => console.log(error));

Python (Requests)

import requests
import json

url = "https://go.getblock.io/<ACCESS-TOKEN>/"

payload = json.dumps({
    "jsonrpc": "2.0",
    "method": "subnetInfo_getLockCost",
    "params": [],
    "id": "getblock.io"
})

headers = {
    'Content-Type': 'application/json'
}

response = requests.post(url, headers=headers, data=payload)
print(response.text)

Rust (Reqwest)

use reqwest::Client;
use serde_json::json;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = Client::new();

    let payload = json!({
        "jsonrpc": "2.0",
        "method": "subnetInfo_getLockCost",
        "params": [],
        "id": "getblock.io"
});

    let response = client
        .post("https://go.getblock.io/<ACCESS-TOKEN>/")
        .header("Content-Type", "application/json")
        .json(&payload)
        .send()
        .await?;

    let result: serde_json::Value = response.json().await?;
    println!("{:#?}", result);

    Ok(())
}

Response Example

{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": "100000000000000"
}

Response Parameters

Field	Type	Description
result	string	Current subnet registration lock cost in rao (1 TAO = 10^9 rao). Example value 100000000000000 rao = 100,000 TAO

Use Cases

• Pre-flight check before submitting a register-network extrinsic

• Tracking subnet creation economics over time

• Subnet launchpad UIs showing live cost to potential subnet creators

Error Handling

Status Code	Error Message	Cause
403	Forbidden	Missing or invalid <ACCESS-TOKEN>
-32602	Invalid params	Request parameters are missing or malformed
-32601	Method not found	Method does not exist on this interface — check whether you're calling a Substrate method on an EVM endpoint or vice versa
-32603	Internal error	Server-side error while processing the request
429	Too Many Requests	Rate limit exceeded for your plan

SDK Integration

Bittensor SDK (Python)

import bittensor as bt

# Bittensor SDK provides typed wrappers for chain-specific data.
# The subtensor client routes to the appropriate custom RPC under the hood:
subtensor = bt.subtensor(network="finney")  # or pass GetBlock URL

# Example for subnetInfo_getSubnetInfo:
# subnet_info = subtensor.get_subnet_info(netuid=1)
# print(subnet_info)

# Or use the raw RPC interface for any custom method:
result = subtensor.substrate.rpc_request("subnetInfo_getLockCost", [])
print(result)

Polkadot.js raw (TypeScript)

import { ApiPromise, WsProvider } from '@polkadot/api';

const provider = new WsProvider('wss://go.getblock.io/<ACCESS-TOKEN>/');
const api = await ApiPromise.create({ provider });

// Bittensor-specific RPCs need the raw send() interface
// (they aren't part of standard Polkadot.js typed wrappers):
const result = await api.rpc.send({
    method: 'subnetInfo_getLockCost',
    params: []
});
console.log(result);