# Phantom API — Gas Estimation for EVM Transactions

> Phantom API — Gas Estimation for EVM Transactions is a paid API for AI agents from phantom-api-omega.vercel.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-20).

Estimates the gas cost for an EVM-compatible smart contract call or transfer before submitting it on-chain

## Facts

- Endpoint: POST https://phantom-api-omega.vercel.app/api/degen/gas/estimate?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/phantom-api-gas-estimation-for-evm-transactions-85008f29
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_OGrJTEq_-4zqcP58zoNxm

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 phantom-api-gas-estimation-for-evm-transactions-85008f29 -d '<json body>'
```

Example prompt: Before I send this contract call, estimate the gas cost — the transaction is from 0xAbC...123 to 0xDef...456, with this calldata: 0xa9059cbb000...000, and no ETH value attached.

## When to prefer this

Use this endpoint when you need a quick, pay-per-call gas estimate for EVM transactions across 57+ networks without managing your own RPC node infrastructure. Prefer it over running your own eth_estimateGas RPC call when you want a hosted, low-latency solution with simple HTTP semantics and micro-payment billing.

## Known failure modes

- Invalid or malformed Ethereum address in 'to' or 'from' fields — returns error
- Invalid hex calldata in 'data' field — returns parsing error
- Transaction would revert on-chain — gas estimation may fail with revert reason
- Network or RPC connectivity issues — returns 5xx error
- Missing required fields — returns 400 validation error

## How this service works

Lightning-fast access to blockchain data, smart contract insights, and Web3 infrastructure across 57+ networks. Pay-per-call via x402.

## Output

Returns an estimated gas amount (in gas units) required to execute the specified transaction, allowing the caller to budget fees and detect potential out-of-gas failures before submission.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "to": {
   "type": "string"
  },
  "data": {
   "type": "string"
  },
  "from": {
   "type": "string"
  },
  "value": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/phantom-api-gas-estimation-for-evm-transactions-85008f29/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from phantom-api-omega.vercel.app](https://www.zero.xyz/host/phantom-api-omega.vercel.app/llms.txt)