system_properties | Kusama RPC Docs

Get chain properties on Kusama including token symbol, decimals, and the address-format prefix when the chain exposes one. Essential for token formatting, wallet configuration, and address handling.

Returns the chain-specific properties for Kusama, including the native token symbol, token decimals, and the address-format prefix when the chain exposes one. This information is critical for correctly formatting balances, validating addresses, and configuring wallets.

Why Kusama? Build on Polkadot's canary network for real-world testing with live economic conditions with 7-day governance cycles (vs 1 month on Polkadot), lower bonding requirements, live KSM token economy, and first-to-market feature testing.

When to Use This Method

system_properties is essential for experimental dApp developers, parachain teams, and early adopters validating new features:

Token Formatting -- Get the correct decimals and symbol to display human-readable balances on Kusama
Address Validation -- Retrieve the SS58 prefix to encode and validate addresses for parachain experimentation, early feature deployment, and production-grade testing with real value
Wallet and dApp Configuration -- Dynamically configure your UI with the correct token symbol, decimals, and address format
Multi-Chain Support -- Automatically adapt your application to different Substrate chains without hardcoding properties

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

async function formatBalance(api, rawBalance) {
  const properties = await api.rpc.system.properties();
  const raw = properties.toJSON();
  const decimalsRaw = raw.tokenDecimals;
  const symbolRaw = raw.tokenSymbol;
  const decimals = Array.isArray(decimalsRaw) ? decimalsRaw[0] : decimalsRaw;
  const symbol = Array.isArray(symbolRaw) ? symbolRaw[0] : symbolRaw;

  const divisor = new BN(10).pow(new BN(decimals));
  const whole = new BN(rawBalance).div(divisor);
  const fractional = new BN(rawBalance).mod(divisor).toString().padStart(decimals, '0');

  return `${whole}.${fractional.slice(0, 4)} ${symbol}`;
}

// Example output depends on the chain's live token symbol and decimals.

2. Dynamic Wallet Configuration

Auto-configure your wallet or dApp based on chain properties:

JavaScript

async function configureWallet(endpoint) {
  const provider = new WsProvider(endpoint);
  const api = await ApiPromise.create({ provider });

  const [chain, properties] = await Promise.all([
    api.rpc.system.chain(),
    api.rpc.system.properties()
  ]);

  const raw = properties.toJSON();
  const symbolsRaw = raw.tokenSymbol;
  const decimalsRaw = raw.tokenDecimals;
  const symbols = Array.isArray(symbolsRaw) ? symbolsRaw : [symbolsRaw];
  const decimals = Array.isArray(decimalsRaw) ? decimalsRaw : [decimalsRaw];
  const ss58Format = raw.ss58Format ?? raw.SS58Prefix ?? null;

  const config = {
    chainName: chain.toString(),
    ss58Format,
    tokens: symbols.map((symbol, idx) => ({
      symbol,
      decimals: decimals[idx] ?? decimals[0],
    }))
  };

  console.log('Wallet configured for:', config.chainName);
  console.log('Native token:', config.tokens[0].symbol, `(${config.tokens[0].decimals} decimals)`);
  console.log('Address format SS58:', config.ss58Format ?? 'not exposed');

  await api.disconnect();
  return config;
}

3. SS58 Address Encoding and Validation

Use the SS58 prefix to properly encode addresses for the target chain:

JavaScript

import { encodeAddress, decodeAddress } from '@polkadot/util-crypto';

async function formatAddressForChain(api, genericAddress) {
  const properties = await api.rpc.system.properties();
  const raw = properties.toJSON();
  const ss58Format = raw.ss58Format ?? raw.SS58Prefix;

  if (ss58Format == null) {
    throw new Error('This chain does not expose an SS58 prefix through system_properties.');
  }

  // Convert any SS58 address to this chain's format
  const publicKey = decodeAddress(genericAddress);
  const chainAddress = encodeAddress(publicKey, ss58Format);

  console.log(`Address on ${ss58Format}: ${chainAddress}`);
  return chainAddress;
}

Error Handling

Common errors and solutions:

Error Code	Description	Solution
-32603	Internal error	Node may be starting up -- retry after delay
-32005	Rate limit exceeded	Reduce request frequency or implement client-side rate limiting
Connection refused	Node unreachable	Verify the RPC endpoint URL and that the node is running
Empty or alternate result fields	Chain spec missing properties or using `SS58Prefix`	Normalize scalar vs array values and fall back to `SS58Prefix` when `ss58Format` is absent

system_chain -- Get the chain name
system_name -- Get the node implementation name
system_version -- Get the node implementation version
state_getMetadata -- Get full runtime metadata including pallet definitions
rpc_methods -- List all available RPC methods

system_properties - Kusama RPC Method

When to Use This Method

Code Examples

Common Use Cases

1. Human-Readable Balance Formatting

2. Dynamic Wallet Configuration

3. SS58 Address Encoding and Validation

Error Handling

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