{"uid":"cap_lCXyfHKwA0S5qZwCd-ZML","slug":"x402-agentutility-ai-1fbd142b","name":"x402 Gas Oracle — EIP-1559 Fee Estimator (Base + Ethereum + Optimism + Arbitrum + Polygon)","description":"Gas oracle / gas price API / EIP-1559 fee estimator / Base + Ethereum + Optimism + Arbitrum + Polygon gas tracker / etherscan-gas alternative / pre-tx cost estimator / USD gas-cost calculator / safe-low + standard + fast tier feed. Reads the chain's latest block, derives the EIP-1559 base fee, suggests priority fees for safe-low / standard / fast tiers, computes the total recommended maxFeePerGas, and converts cost to USD for common tx types (transfer, ERC-20 transfer, Uniswap swap, NFT mint).","url":"https://x402.agentutility.ai/gas-now-base","method":"POST","headers":{},"bodySchema":{"$schema":"https://json-schema.org/draft/2020-12/schema","type":"object","properties":{"input":{"type":"object","properties":{"type":{"type":"string","const":"http"},"method":{"type":"string","enum":["POST"]},"bodyType":{"type":"string","enum":["json","form-data","text"]},"body":{"properties":{"chain":{"type":"string","enum":["base","ethereum","optimism","arbitrum","polygon"],"description":"EVM L1/L2 to read gas from. Default 'base'."}}}},"required":["type","method","bodyType","body"],"additionalProperties":false},"output":{"type":"object","properties":{"type":{"type":"string"},"example":{"type":"object","properties":{"chain":{"type":"string"},"base_fee_gwei":{"type":"number"},"priority_fee_gwei":{"type":"object","properties":{"safe_low":{"type":"number"},"standard":{"type":"number"},"fast":{"type":"number"}}},"total_recommended_gwei":{"type":"number"},"block_number":{"type":"integer"},"eth_price_usd":{"type":"integer"},"cost_usd":{"type":"object","properties":{"transfer":{"type":"number"},"erc20_transfer":{"type":"number"},"uniswap_swap":{"type":"number"},"nft_mint":{"type":"number"}}},"timestamp":{"type":"string"}}}},"required":["type"]}},"required":["input"]},"responseSchema":{"type":"json","example":{"chain":"base","cost_usd":{"nft_mint":0.006,"transfer":0.0008,"uniswap_swap":0.004,"erc20_transfer":0.0012},"timestamp":"2026-05-06T22:00:00Z","block_number":27500000,"base_fee_gwei":0.005,"eth_price_usd":3500,"priority_fee_gwei":{"fast":0.002,"safe_low":0.001,"standard":0.001},"total_recommended_gwei":0.006}},"example":{"request":{"chain":"base","transactionTypes":["uniswap_swap","token_transfer","contract_deployment"]},"response":{"chain":"base","rpc_url":"https://mainnet.base.org","chain_id":"8453","block_number":"47423183","native_token":"ETH","base_fee_gwei":0.005,"cost_estimates":{"nft_mint":{"gas":100000,"usd_cost":null,"native_cost":6e-7},"erc20_approve":{"gas":50000,"usd_cost":null,"native_cost":3e-7},"usdc_transfer":{"gas":65000,"usd_cost":null,"native_cost":3.9e-7},"contract_deploy":{"gas":500000,"usd_cost":null,"native_cost":0.000003},"native_transfer":{"gas":21000,"usd_cost":null,"native_cost":1.26e-7},"uniswap_v2_swap":{"gas":120000,"usd_cost":null,"native_cost":7.2e-7},"uniswap_v3_swap":{"gas":150000,"usd_cost":null,"native_cost":9e-7}},"block_timestamp":1781635713,"block_age_seconds":2,"block_iso_timestamp":"2026-06-16T18:48:33.000Z","legacy_gas_price_gwei":0.006,"native_token_price_usd":null,"total_recommended_gwei":0.006,"priority_fee_suggestion_gwei":0.001}},"exampleRequest":{"chain":"base","transactionTypes":["uniswap_swap","token_transfer","contract_deployment"]},"tags":["x402"],"displayCostAmount":"0.02","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"settled","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":"$0.02/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_7wpunv_Pbb91cwLIW0ZPW","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.02","costPer":"request","priority":0,"asset":null,"unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Reads the latest block on a specified EVM chain, derives EIP-1559 base fee, suggests priority fees for safe-low/standard/fast tiers, computes maxFeePerGas, and converts gas costs to USD for common transaction types.","exampleAgentPrompt":"What are the current gas fees on Base — give me the safe-low, standard, and fast EIP-1559 tiers and tell me how much a Uniswap swap would cost in USD right now?","exampleUseCases":null,"resultDescription":"Returns the current EIP-1559 base fee from the latest block, suggested priority fees (tip) for safe-low, standard, and fast tiers, the computed maxFeePerGas for each tier, and USD cost estimates for common transaction types including ETH transfer, ERC-20 transfer, Uniswap swap, and NFT mint.","failureModes":["Unsupported chain name returns an error or empty response","Chain RPC unavailable causes timeout or error","Stale block data if chain has reorg or is congested","Missing or invalid chain parameter returns 400-level error","USD conversion may be stale if price feed is delayed"],"whenToPreferThis":"Use this endpoint when you need real-time EIP-1559 gas estimates on Base, Ethereum, Optimism, Arbitrum, or Polygon — especially when you want USD cost breakdowns for specific transaction types like swaps or NFT mints. Prefer this over Etherscan gas tracker when you need multi-chain coverage in a single API call with USD conversion included.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T13:13:36.612Z","isFirstParty":false}