# Phantom API – Aptos Gas Estimator

> Phantom API – Aptos Gas Estimator 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 2026-09-14).

Estimates gas fees for a transaction on the Aptos blockchain given sender, recipient, value, and calldata.

## Facts

- Endpoint: POST https://phantom-api-omega.vercel.app/api/aptos/gas/estimate
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/phantom-api-aptos-gas-estimator-0ee2172b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_oChwqpmQUTl5pRMcxx27x

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-aptos-gas-estimator-0ee2172b -d '<json body>'
```

Example prompt: Estimate the gas fee for an Aptos transaction from address 0xabc...123 to 0xdef...456, sending 1 APT with calldata 0x00.

## When to prefer this

Use this endpoint when you need a fast, pay-per-call gas estimate for Aptos transactions without running your own Aptos node or managing RPC infrastructure. It's ideal for agents, bots, or wallets that need real-time fee preflight checks across the Aptos network with minimal setup.

## Known failure modes

- Invalid or malformed Aptos address returns an error response
- Missing required fields (e.g. no sender or recipient) may cause a 400 bad request
- Aptos RPC node unavailability may result in a timeout or 503 error
- Unsupported transaction data encoding may return an estimation error
- Payment of $0.01 USDC via x402 not provided or rejected results in a 402 response

## 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 fee for the described Aptos transaction, allowing callers to budget network costs before submitting the transaction on-chain.

## 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-aptos-gas-estimator-0ee2172b/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)