{"uid":"cap_Xne6D1ji6umjEc2rOYhZk","slug":"fastpath-api-bitcoin-fee-estimate-01b3f5bf","name":"FastPath API - Bitcoin Fee Estimate","description":"FastPath translates Ethereum-style JSON-RPC requests into Bitcoin data, fee intelligence, mempool insight, and Core v31 package signals. Paid by x402.","url":"https://api.nativebtc.org/v1/fee-estimate","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":{"blocks":{"type":"number","minimum":1,"description":"Confirmation target in blocks. Defaults to 6."}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"satVb":1,"blocks":6,"source":"bitcoin_core_estimatesmartfee","success":true}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.001","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":"$0.001/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_wHSkPM1oMEb-iL7wPtpk5","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.001","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns a Bitcoin fee estimate in sat/vB for a given confirmation target (in blocks), sourced from Bitcoin Core's estimatesmartfee.","exampleAgentPrompt":"What's the current Bitcoin fee estimate to get confirmed within 6 blocks? Give me the sat/vB rate from Bitcoin Core.","exampleUseCases":[{"title":"Optimizing wallet transaction fees","prompt":"I'm about to send a Bitcoin transaction — what fee rate in sat/vB should I use to get it confirmed within 3 blocks?"},{"title":"DCA bot pre-send fee check","prompt":"Before my weekly Bitcoin purchase goes out, check what the current recommended fee rate is so I don't overpay — targeting a 6-block confirmation."},{"title":"Fee spike alerting for an exchange","prompt":"What's the Bitcoin Core fee estimate right now for a 1-block confirmation? I want to know if fees have spiked above normal."}],"resultDescription":"Returns a JSON object with the estimated fee rate in sat/vB (satVb), the confirmation target in blocks (blocks), the data source identifier (bitcoin_core_estimatesmartfee), and a success boolean.","failureModes":["Invalid or missing blocks parameter returns an error or falls back to default (6 blocks)","Bitcoin Core node unavailable may return a 503 or error response","Payment not processed (x402 flow incomplete) results in a 402 Payment Required response","Blocks value below minimum (1) rejected by schema validation","Network congestion or mempool instability may cause unusual fee estimates"],"whenToPreferThis":"Use this endpoint when you need a reliable, Bitcoin Core-native fee estimate in sat/vB format and want a simple REST GET interface rather than running your own node or calling JSON-RPC directly. It's especially suited for agents or apps already familiar with Ethereum-style APIs but operating on Bitcoin. Prefer it over mempool.space scraping when you want a structured, paid, programmatic feed sourced from Bitcoin Core's own estimatesmartfee logic.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T00:42:01.839Z","isFirstParty":false}