---
title: "Paid: Ethereum Gas Oracle"
method: GET
path: "/api/x402/market-gas"
---

# Paid: Ethereum Gas Oracle

`GET /api/x402/market-gas`

## Request

- Base URL: `https://three.ws`
- URL: `https://three.ws/api/x402/market-gas`
- Auth: none required

Live Ethereum gas oracle for agents — pay $0.001 USDC per call. Computes slow/standard/fast tiers from eth_feeHistory over the last ~20 blocks (base fee + 25th/50th/90th priority-fee percentiles, median-smoothed) across failover public RPCs — no third-party gas API. Each tier carries USD cost estimates for an ETH transfer, token transfer, DEX swap, and NFT mint at the live ETH price. Same oracle behind three.ws/gas.

## Response `200`

three.ws Market Data result JSON

## Other responses

- `400`: Validation error
- `402`: Payment Required (x402)

---

[API](https://skmtc.dev/three/apis/three-ws-api.md) · [All operations](https://skmtc.dev/three/apis/three-ws-api/llms.txt) · [OpenAPI document](https://skmtc.dev/three/apis/three-ws-api/revisions/dbc5e3a81b79?raw)