net_version — Polygon JSON-RPC

Status: Available

Returns the network ID as a decimal string — "137" for Polygon mainnet.

POSThttps://triport.io/polygon

Network: Polygon
Scope: polygon_read_rpc
Auth: x-token: $TRIPORT_API_KEY (or Authorization: Bearer)
Rate limit: free — 15 RPS sustained · up to 30 burst · basic — 20 RPS sustained · up to 40 burst · pro — 100 RPS sustained · up to 200 burst · business — 250 RPS sustained · up to 500 burst; Burst capacity

Endpoint and plans: Polygon RPC endpoint. Chain check: expected Polygon value and how to check it.

Request

cURLJavaScriptPython

curl https://triport.io/polygon \
  -H "Authorization: Bearer $TRIPORT_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "net_version",
    "params": []
  }'

const res = await fetch("https://triport.io/polygon", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${process.env.TRIPORT_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "jsonrpc": "2.0",
    "id": 1,
    "method": "net_version",
    "params": []
  }),
});
const data = await res.json();
console.log(data);

import os


import requests


resp = requests.post(
    "https://triport.io/polygon",
    headers={
        "Authorization": f"Bearer {os.environ['TRIPORT_API_KEY']}",
        "Content-Type": "application/json",
    },
    json={
        "jsonrpc": "2.0",
        "id": 1,
        "method": "net_version",
        "params": [],
    },
)
data = resp.json()
print(data)

Response

JSON

Example

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "137"
}

net_version returns the network identifier of the connected chain as a decimal string. For Polygon mainnet the value is "137".

This is a legacy companion to eth_chainId: both identify the chain, but net_version returns a decimal string ("137") while eth_chainId returns a hex quantity (0x89). Web3.js versions before 4.x call net_version during network detection, which is the main reason to keep it around. For new integrations prefer eth_chainId — it is the EIP-155 chain ID used for replay-protected transaction signing.

This method takes no parameters and is available on every tier (polygon_read_rpc).

Parameters

This method takes no parameters.

——optional

Pass an empty array [] as params.

Response

Response fields

Field	Type	Description
`result`	string	Network ID as a decimal string. `"137"` is Polygon mainnet.

Errors

Code	Meaning	When it happens
`401`	`trial_expired`	The API key's trial period has ended; upgrade to a paid tier to continue.
`403`	`tier_insufficient`	Your tier does not include the `polygon_read_rpc` scope.
`429`	`rate_limited`	You exceeded the requests-per-second limit for your tier. Back off and retry.
`401`	`subscription_expired`	The subscription tied to the API key has lapsed.
`401`	`unauthorized`	Missing or invalid API key.
HTTP `403`	`method_unknown`	The method is not available on the resolved upstream for your request.

Errors are returned in the standard JSON-RPC envelope. See the shared errors reference for the full error object shape and handling guidance.

Examples

JavaScript (fetch)

JavaScript

const res = await fetch("https://triport.io/polygon", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${process.env.TRIPORT_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    jsonrpc: "2.0",
    id: 1,
    method: "net_version",
    params: [],
  }),
});


const { result } = await res.json();
console.log(result);              // "137"
console.log(Number(result));      // 137

Notes

The result is a decimal string, not a hex quantity — convert with Number(result) (JS) or int(result) (Python). This differs from eth_chainId, which returns the hex quantity 0x89.
The network ID is stable for the lifetime of the chain and never changes between blocks, so the value is safe to cache for the duration of a session.
Polygon Amoy testnet returns "80002".
Related: eth_chainId is the preferred chain-detection method for modern clients; net_listening and net_peerCount cover the rest of the net namespace.