# Multi-Chain Gas Price Tracker (USD-Normalized)

> Multi-Chain Gas Price Tracker (USD-Normalized) is a paid API for AI agents from x402.donnyautomation.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Returns live gas prices across 6 EVM chains (BNB Chain, Polygon, Arbitrum, Base, Avalanche, Optimism) in gwei, base fee, and USD cost for transfers, ERC-20 transfers, and swaps, sorted cheapest-first.

## Facts

- Endpoint: GET https://x402.donnyautomation.com/gas
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/multi-chain-gas-price-tracker-usd-normalized-4e26b77a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Nu9AgiAQ-4CJFjUnee4NB

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 multi-chain-gas-price-tracker-usd-normalized-4e26b77a
```

Example prompt: Which blockchain has the cheapest gas right now for a token swap — compare BNB Chain, Polygon, Arbitrum, Base, Avalanche, and Optimism and show me the USD cost for each, ranked cheapest-first.

## When to prefer this

Use this endpoint when you need USD-normalized gas cost comparisons across multiple EVM chains simultaneously — particularly for routing, bridging, or execution-timing decisions where raw gwei figures are misleading because gas token prices differ. Prefer this over chain-specific gas APIs when the goal is cross-chain ranking rather than monitoring a single network.

## Known failure modes

- Missing or invalid chain parameter results in paywall redirect — always pass chain=all or a specific chain name
- Invalid chain value (e.g. 'ethereum') returns an error; only bsc, polygon, arbitrum, base, avalanche, optimism are valid
- RPC outage on one or more chains may cause partial results or stale data
- Payment failure (x402) blocks access if USDC balance is insufficient
- Network latency from on-chain RPC reads may occasionally return slightly stale gas data

## How this service works

Live gas price on BNB Chain, Polygon, Arbitrum, Base, Avalanche and Optimism, converted to USD and ranked cheapest-first. Gwei is NOT comparable across chains because the gas token differs in price; USD is the only honest ranking. Returns chains[] with gasPriceGwei, baseFeeGwei, nativeUsd and costUsd for transfer, erc20Transfer and swap, plus cheapest and mostExpensive. Optional ?chain=all or one chain key; 400 unknown_chain otherwise. Send chain=all - a bare call skips the free tier.

## Output

A JSON array of chain objects sorted cheapest-first, each containing: chain name, gas price in gwei, base fee, and the USD cost of a standard native transfer, an ERC-20 transfer, and a DEX swap. Enables direct USD-denominated comparison across chains without needing to account for differing gas token prices.

## 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"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [],
     "properties": {
      "chain": {
       "type": "string",
       "description": "Pass `all` for every chain ranked cheapest-first, or one of bsc, polygon, arbitrum, base, avalanche, optimism. Omitting it also returns all six, but a parameterless request is treated as a catalogue crawler and goes straight to the paywall — send chain=all to use the free tier."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ts": "2026-07-31T00:00:00.000Z",
  "chainId": 56,
  "network": "bsc"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/multi-chain-gas-price-tracker-usd-normalized-4e26b77a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.donnyautomation.com](https://www.zero.xyz/host/x402.donnyautomation.com/llms.txt)