# Ethereum Mainnet ETH Balance (eth_getBalance)

> Ethereum Mainnet ETH Balance (eth_getBalance) is a paid API for AI agents from api.arysphere.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-17).

Returns the native ETH balance in wei for a given Ethereum mainnet address using eth_getBalance.

## Facts

- Endpoint: GET https://api.arysphere.com/v1/ventures/x402_eth_reads_v1/eth_mainnet_eth_getbalance?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-17
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/ethereum-mainnet-eth-balance-eth-getbalance-9d216e96
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_gB5sy3mWVtyeB0WtGq5PZ

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability ethereum-mainnet-eth-balance-eth-getbalance-9d216e96
```

Example prompt: What's the current ETH balance of the Ethereum mainnet address 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045? Give me the result in wei.

## When to prefer this

Choose this endpoint when you need a quick, paid, permissionless read of a native ETH balance on Ethereum mainnet without managing your own RPC node or API key. It is ideal for AI agents operating in x402 payment-capable environments that need on-chain data with minimal setup. Prefer this over self-hosted RPC calls when you want a metered, reliable mainnet read with a simple REST interface.

## Known failure modes

- Invalid address format (not 0x + 40 hex) causes a validation error
- Address with zero balance returns 0x0 hex and result: 0 — not an error
- Network timeouts or RPC node unavailability may cause failed reads
- Payment failure (x402 protocol) if USDC balance is insufficient for the $0.003 fee
- Malformed request missing required address query param returns an error response

## How this service works

ARYSPHERE sells AI-written verdicts on Base token contracts (a grade, a one-liner, a roast and the contract's facts) and Base/Ethereum chain reads, paid per call in USDC on Base over x402 v2. No account and no API key.

## Output

A JSON object containing: ok (boolean success flag), hex (balance in hexadecimal wei), result (numeric balance in wei), chain (chain identifier, e.g. 'base' or 'eth'), method ('eth_getBalance'), and service name string.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "address": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{40}$",
       "description": "0x + 40 hex"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "hex": "0x50122e9e75120cc5",
  "chain": "ethereum",
  "method": "eth_getBalance",
  "result": 5769725330718854000,
  "service": "x402_eth_reads_v1.eth_mainnet_eth_getbalance"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/ethereum-mainnet-eth-balance-eth-getbalance-9d216e96/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.arysphere.com](https://www.zero.xyz/host/api.arysphere.com/llms.txt)