Polygon

Endpoint	https://rpc.lab.au.ro/polygon
Protocol	JSON-RPC 2.0 over HTTPS (POST)
chainId	137 (0x89)
Batch	✓

Supported methods

Same live-verified EVM surface as Ethereum, plus Polygon's bor_* namespace is reachable where the node exposes it. debug_*/trace_* are not available.

Quick test

curl -X POST https://rpc.lab.au.ro/polygon \
  -H "apikey: $YOUR_API_KEY" -H 'Content-Type: application/json' \
  -d '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}'
# {"jsonrpc":"2.0","id":1,"result":"0xfe60b6"}

SDK integration

import { createPublicClient, http } from 'viem'
import { polygon } from 'viem/chains'

const client = createPublicClient({
  chain: polygon,
  transport: http('https://rpc.lab.au.ro/polygon', {
    fetchOptions: { headers: { apikey: process.env.YOUR_API_KEY } }
  })
})
console.log(await client.getChainId())   // 137

ethers v6: same FetchRequest pattern as Ethereum.

Recipes

• MATIC/POL balance — eth_getBalance, native token semantics identical to ETH.
• Fee estimation — use eth_maxPriorityFeePerGas + eth_feeHistory; Polygon enforces a 25–30 gwei priority floor most of the time.

Limitations

• Pruned node; no archive queries.
• Polygon reorgs more than Ethereum — wait extra confirmations (eth_getTransactionReceipt + block depth) before treating value as final.