Crypto Balance

Query native token balances (ETH, MATIC, etc.) on EVM-compatible chains.

Prerequisites

For reliable queries, set ALCHEMY_API_KEY in your environment. Without it, use public RPCs (may be rate-limited).

Quick Balance Check

Use exec with curl to query via JSON-RPC:

bash

# Check ETH balance on Ethereum mainnet (public RPC)
curl -s -X POST https://eth.llamarpc.com \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_getBalance","params":["0xYOUR_ADDRESS","latest"],"id":1}'

With Alchemy (recommended)

bash

# Ethereum
curl -s -X POST "https://eth-mainnet.g.alchemy.com/v2/${ALCHEMY_API_KEY}" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_getBalance","params":["0xYOUR_ADDRESS","latest"],"id":1}'

# Polygon
curl -s -X POST "https://polygon-mainnet.g.alchemy.com/v2/${ALCHEMY_API_KEY}" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_getBalance","params":["0xYOUR_ADDRESS","latest"],"id":1}'

# Arbitrum
curl -s -X POST "https://arb-mainnet.g.alchemy.com/v2/${ALCHEMY_API_KEY}" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_getBalance","params":["0xYOUR_ADDRESS","latest"],"id":1}'

# Base
curl -s -X POST "https://base-mainnet.g.alchemy.com/v2/${ALCHEMY_API_KEY}" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_getBalance","params":["0xYOUR_ADDRESS","latest"],"id":1}'

Public RPC Endpoints (No API Key)

Chain	RPC URL
Ethereum	`https://eth.llamarpc.com`
Polygon	`https://polygon-rpc.com`
Arbitrum	`https://arb1.arbitrum.io/rpc`
Base	`https://mainnet.base.org`

Response Format

json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x1bc16d674ec80000"  // Balance in wei (hex)
}

Converting Wei to ETH

The result is in wei (hex). To convert:

bash

# Using Python
python3 -c "print(int('0x1bc16d674ec80000', 16) / 1e18)"
# Output: 2.0 (ETH)

Native Token Symbols

Chain	Symbol
Ethereum	ETH
Polygon	MATIC
Arbitrum	ETH
Base	ETH

Address Validation

Valid EVM address format: 0x followed by 40 hex characters

•✅ 0x742d35Cc6634C0532925a3b844Bc9e7595f85a3d
•❌ 742d35Cc6634C0532925a3b844Bc9e7595f85a3d (missing 0x)
•❌ 0x742d35Cc (too short)

Example Workflow

•User asks: "What's the ETH balance of 0x742d35Cc6634C0532925a3b844Bc9e7595f85a3d?"
•Validate address format
•Run curl command against Ethereum RPC
•Convert hex result to decimal, divide by 1e18
•Reply: "Address 0x742d...5a3d has 2.5 ETH on Ethereum mainnet"