# Genexxis Gas Comparison — Multi-Chain EVM Gas Cost Comparator

> Genexxis Gas Comparison — Multi-Chain EVM Gas Cost Comparator is a paid API for AI agents from gas.genexxis.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-11-04).

Returns the USD cost of a transaction (by gas units) across Ethereum, Base, Arbitrum, OP Mainnet, Polygon, and BNB Chain sorted cheapest-first, with slow/standard/fast speed tiers.

## Facts

- Endpoint: GET https://gas.genexxis.com/compare?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-11-04
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/genexxis-gas-comparison-multi-chain-evm-gas-cost-comparator-8bb1179b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_qMdXLRSyQ94SR736tarKp

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 genexxis-gas-comparison-multi-chain-evm-gas-cost-comparator-8bb1179b
```

Example prompt: What would a 65,000 gas transaction cost right now on each major EVM chain — Ethereum, Base, Arbitrum, Optimism, Polygon, and BNB — broken down by slow, standard, and fast speed, sorted cheapest first?

## When to prefer this

Use this endpoint when you need a real-time, side-by-side USD cost comparison of a specific transaction across all major EVM chains at once, with slow/standard/fast tiers. Prefer it over single-chain gas endpoints when the goal is chain selection or cost optimization rather than just knowing the current gas price on one specific network.

## Known failure modes

- Invalid gas units outside 21000–30000000 range may return an error or default to 65000
- One or more chains may appear in the 'failed' array if their RPC is temporarily unavailable
- Stale or cached gas prices if blockchain RPCs are slow to respond
- HTTP 402 if payment header is missing or USDC payment fails

## How this service works

What a transaction costs right now, in USD, on Ethereum, Base, Arbitrum, OP Mainnet, Polygon and BNB Chain. Live from public RPCs (eth_feeHistory over the last 20 blocks: base fee + slow/standard/fast priority fees), native token prices from Coinbase/Binance, and the L1 data fee for rollups (OP-stack GasPriceOracle, Arbitrum ArbGasInfo). Gives USD cost for a native transfer, an ERC-20 transfer and a Uniswap-style swap, or compares all 6 chains for any gas amount. Cached 15 s.

## Output

A JSON object containing the input gas units, an array of chains (optimism, base, bsc, ethereum, arbitrum, polygon) each with a costUsd object showing slow/standard/fast prices in USD and the native token symbol, sorted cheapest first, plus a 'failed' array listing any chains that could not be fetched.

## 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": {
      "gas": {
       "type": "string",
       "description": "gas units of the transaction (21000-30000000), default 65000"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "gas": 65000,
  "chains": [
   {
    "chain": "optimism",
    "costUsd": {
     "fast": 0.000763,
     "slow": 0.00000167,
     "standard": 0.0000169
    },
    "nativeToken": "ETH"
   },
   {
    "chain": "base",
    "costUsd": {
     "fast": 0.00229,
     "slow": 0.000817,
     "standard": 0.000938
    },
    "nativeToken": "ETH"
   },
   {
    "chain": "bsc",
    "costUsd": {
     "fast": 0.00476,
     "slow": 0.00238,
     "standard": 0.00238
    },
    "nativeToken": "BNB"
   },
   {
    "chain": "ethereum",
    "costUsd": {
     "fast": 0.159,
     "slow": 0.00691,
     "standard": 0.00753
    },
    "nativeToken": "ETH"
   }
  ],
  "failed": []
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/genexxis-gas-comparison-multi-chain-evm-gas-cost-comparator-8bb1179b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from gas.genexxis.com](https://www.zero.xyz/host/gas.genexxis.com/llms.txt)