{"uid":"cap_iZxIfYw3fCfBfj0kropj6","slug":"x402-gas-fee-oracle-a09003bf","name":"x402 Gas Fee Oracle","description":"Use before sending an EVM transaction to pick the cheapest chain and set its fees. Live gas on Ethereum, Base, Arbitrum, Optimism, Polygon and BSC: slow/standard/fast EIP-1559 fee tiers (priority fee, maxFee) from recent blocks, plus the USD cost of a transfer, ERC-20 transfer and swap per tier, cheapest chain first.","url":"https://x402-tools-production-2755.up.railway.app/tools/gas?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","properties":{"chains":{"type":"string","description":"Comma-separated subset of: ethereum, base, arbitrum, optimism, polygon, bsc. Default: all"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.002","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.002/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_WRXc2Jq213_GUK50AOLvi","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.002","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns live EIP-1559 gas fee tiers (slow/standard/fast) with USD cost estimates for common transaction types across up to 6 EVM chains, sorted cheapest first","exampleAgentPrompt":"Before I send this swap, check current gas fees across Ethereum, Base, Arbitrum, Optimism, Polygon, and BSC — give me the slow/standard/fast EIP-1559 tiers with USD costs for a swap on each chain, sorted by cheapest first.","exampleUseCases":[{"title":"Cheapest chain for a token swap","prompt":"I want to do a token swap but don't want to overpay on gas — which EVM chain is cheapest right now and what will it cost me in USD at the standard speed?"},{"title":"Pre-flight gas check before ERC-20 transfer","prompt":"I'm about to send some USDC to a friend — can you pull the current gas fees on Base and Arbitrum so I can pick the cheaper option, and tell me the USD cost at standard speed?"},{"title":"Fast transaction on Polygon or BSC","prompt":"I need this transaction to confirm quickly on either Polygon or BSC — what are the fast-tier EIP-1559 fees on both right now, and how much will it cost in USD?"}],"resultDescription":"A list of EVM chains sorted cheapest-first, each with slow/standard/fast EIP-1559 fee tiers (priority fee and maxFee in gwei), plus estimated USD costs for a native transfer, ERC-20 transfer, and swap at each speed tier, derived from recent block data.","failureModes":["Upstream RPC node unavailable for a specific chain — that chain may be omitted from results","Stale data if block production is slow on a chain","Invalid chain name in query param returns error or is silently ignored","Network timeout if multiple chains are queried simultaneously under load"],"whenToPreferThis":"Use this endpoint when an agent needs to programmatically choose the most cost-efficient EVM chain or fee tier before submitting a transaction. It is preferred over manual RPC calls because it aggregates live data from 6 chains in one request, converts fees to USD, and ranks chains by cost — eliminating the need to query each chain separately and compute USD conversions.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-02T18:34:33.831Z","isFirstParty":false,"canonicalSlug":"x402-gas-fee-oracle-a09003bf"}