# EVM Gas Estimator — Estimate Gas Usage and Cost

> EVM Gas Estimator — Estimate Gas Usage and Cost is a paid API for AI agents from api.vextorium.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-13).

Estimates how much gas a transaction will consume and its cost at the current gas price across 12 EVM chains, returning the revert reason if the transaction would fail.

## Facts

- Endpoint: POST https://api.vextorium.com/evm-estimar-gas-pago?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/evm-gas-estimator-estimate-gas-usage-and-cost-58195542
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_VBKHTgEMtUdTaYhux5xPH

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 evm-gas-estimator-estimate-gas-usage-and-cost-58195542 -d '<json body>'
```

Example prompt: Before I submit anything, estimate how much gas it would cost to send 0.1 ETH from 0xAbC...123 to 0xDeF...456 on Base — tell me the gas units, gas price in gwei, and the total ETH cost.

## When to prefer this

Use this endpoint when you need to pre-flight check a transaction before submitting it, verify it won't revert, or calculate expected gas costs across 12 supported EVM chains without any risk of sending anything on-chain. Prefer this over live gas price endpoints when you also need per-transaction simulation rather than just current network gas prices.

## Known failure modes

- Invalid sender or recipient address returns an error
- Transaction would revert — response includes revert reason instead of gas estimate
- Unsupported chain specified returns a validation error
- Missing required fields (de or a) returns a schema validation error
- Network congestion or RPC unavailability may cause timeouts
- Malformed calldata (datos field) causes simulation failure

## How this service works

Estimate the gas a transaction will use (eth_estimateGas) and its cost at the current gas price, or the revert reason if it would fail. Nothing is sent. Works on Base, Ethereum, Arbitrum, Optimism, Polygon, BNB Chain, Avalanche, Gnosis, Linea, Scroll, Sonic and Unichain.

## Output

Returns a JSON object with: whether the transaction is executable (true/false), estimated gas units, recommended gas units (with buffer), current gas price in gwei, estimated cost in the chain's native token, the chain name, and the native token symbol. If the transaction would revert, the revert reason is returned instead.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "a": {
   "type": "string"
  },
  "de": {
   "type": "string"
  },
  "red": {
   "enum": [
    "base",
    "ethereum",
    "arbitrum",
    "optimism",
    "polygon",
    "bnb",
    "avalanche",
    "gnosis",
    "linea",
    "scroll",
    "sonic",
    "unichain"
   ],
   "type": "string",
   "description": "Chain (default base)"
  },
  "datos": {
   "type": "string"
  },
  "valor": {
   "type": "number"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "red": "base",
  "nativo": "ETH",
  "ejecutable": true,
  "gas_estimado": 30989,
  "coste_estimado": 1.859e-7,
  "gas_recomendado": 37186,
  "precio_gas_gwei": 0.006
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/evm-gas-estimator-estimate-gas-usage-and-cost-58195542/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.vextorium.com](https://www.zero.xyz/host/api.vextorium.com/llms.txt)