# Phantom API — Gas Estimation

> Phantom API — Gas Estimation 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 2026-10-16).

Estimates the gas cost for an Ethereum-compatible transaction given sender, recipient, data, and value

## Facts

- Endpoint: POST https://phantom-api-omega.vercel.app/api/tempo/gas/estimate?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/phantom-api-gas-estimation-ebd82d5c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_-vPi4zr1QKi0HgNo8yIAO

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-ebd82d5c -d '<json body>'
```

Example prompt: Estimate how much gas it will take to call this contract — sending from 0xAbC...123 to 0xDef...456 with this calldata: 0xa9059cbb000000... and a value of 0 ETH.

## When to prefer this

Use this endpoint when you need a quick, pay-per-call gas estimate for EVM transactions without managing your own RPC node or Web3 provider. Ideal for agents that need to pre-validate transaction costs before signing or submitting, especially across multiple networks. Prefer this over self-hosted solutions when cost-per-call at $0.01 USDC is acceptable and infrastructure management overhead should be minimized.

## Known failure modes

- Invalid address format for 'to' or 'from' fields returns a validation error
- Malformed or non-hex calldata in 'data' field causes parsing failure
- Unsupported network or unavailable RPC may return a 503 or empty response
- Payment not completed (x402 protocol) returns a 402 Payment Required response
- Simulated transaction that would revert on-chain may return an error or revert reason

## 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 described transaction on an EVM-compatible chain, computed by simulating the transaction without broadcasting it.

## 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-ebd82d5c/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)