{"uid":"cap_UGam-hnVim6Do-6-_u7Dv","slug":"gas-price-estimator-multi-chain-evm-gas-fees-x402-933d4b63","name":"Gas Price Estimator — Multi-Chain EVM Gas Fees (x402)","description":"Invoice-to-JSON, on-chain tools (transaction explainer + payment check, wallet profile, contract ABI, ERC-20 token risk), company contacts and web-to-RAG for AI agents. Pay per call with x402 (USDC on Base). No signup, no API key.","url":"https://freetier-agent-api.pages.dev/api/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","required":[],"properties":{"chains":{"type":"string","description":"\"all\" (default) or a comma list: ethereum,base,arbitrum,optimism,polygon"}}}}},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"chains":[{"block":37000000,"chain":"base","chainId":8453,"estimates":{"erc20_transfer":{"gas":65000,"usd":0.0012,"native":"0.00000039"}},"nativeCoin":"ETH","gasPriceGwei":0.006}],"ranking":["base","optimism","arbitrum","polygon","ethereum"],"cheapestForUsdcTransfer":"base"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.0015","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":"$0.0015/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.0015","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.0015","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_Iueyml_-trMLsYWGwxpyi","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.0015","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns current gas price estimates and ERC-20 transfer costs across major EVM chains, ranking them cheapest to most expensive","exampleAgentPrompt":"Which EVM chain is cheapest to send USDC on right now — check across all chains including Ethereum, Base, Arbitrum, Optimism, and Polygon, and tell me the gas price in gwei and estimated USD cost for an ERC-20 transfer on each.","exampleUseCases":[{"title":"Cheapest chain for USDC payment routing","prompt":"I need to send USDC to a vendor — which of Ethereum, Base, Arbitrum, Optimism, or Polygon has the lowest gas fees right now for an ERC-20 transfer, and what will it cost me in USD?"},{"title":"Real-time gas dashboard for all EVM chains","prompt":"Give me the current gas prices across all supported EVM chains — I want the gwei price, the USD cost of an ERC-20 transfer, and how they rank from cheapest to most expensive."},{"title":"Base vs Arbitrum gas comparison","prompt":"Compare current gas fees on Base versus Arbitrum only — what's the gas price in gwei on each and how much would an ERC-20 token transfer cost in USD on each chain?"}],"resultDescription":"Returns a JSON object with an array of chain entries (each including block number, chain name, chain ID, native coin, gas price in gwei, and estimated ERC-20 transfer cost in gas units, USD, and native token), plus a ranked list of chains from cheapest to most expensive and a 'cheapestForUsdcTransfer' field indicating the optimal chain.","failureModes":["Invalid chain name in 'chains' parameter returns an error or empty result","Network latency causes stale gas price data for fast-moving chains like Ethereum mainnet","x402 payment failure if USDC balance on Base is insufficient","Cloudflare Pages cold-start latency on first request"],"whenToPreferThis":"Use this endpoint when an AI agent needs to programmatically decide which EVM chain to use for a token transfer based on current gas costs, or when building a gas fee dashboard. It covers the five major EVM chains (Ethereum, Base, Arbitrum, Optimism, Polygon) in a single call. Prefer it over chain-specific RPC calls when you need cross-chain comparison without managing multiple providers. Requires pay-per-call with USDC via x402 — no API key needed.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-30T12:31:28.685Z","isFirstParty":false,"canonicalSlug":"gas-price-estimator-multi-chain-evm-gas-fees-x402-933d4b63"}