{"uid":"cap_-Heua6GAOnU5x6-pUg5Py","slug":"asn-lookup-3d3e588b","name":"ASN Lookup","description":"Given an internet address (IP) or a network identification number (ASN), this tool returns who operates that piece of the internet: the network number, the owner's name, the country it's registered in, the regional registry that manages it, and the exact address range it belongs to.","url":"https://asn-lookup.underscoredone.com/lookup","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"query":{"type":"string","description":"An IP address (such as 8.8.8.8 or 2001:4860:4860::8888) or an ASN reference (such as AS15169 or 15169) to look up."}}},"responseSchema":{"type":"json","example":{"asn":"AS15169","query":"8.8.8.8","holder":"GOOGLE","prefix":"8.8.8.0/24","country":"US","registry":"arin","allocated":"1992-12-01","api_version":"1.0.0"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","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":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_3ocbJSkQum_n2E8VnvHRL","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns network owner, prefix, country, and registry details for a given IP address or ASN identifier.","exampleAgentPrompt":"Who owns the IP address 8.8.8.8 — what's the ASN, network holder, country, and prefix?","exampleUseCases":null,"resultDescription":"A JSON object containing the ASN (e.g. AS15169), the original query, the network holder name (e.g. GOOGLE), the IP prefix (e.g. 8.8.8.0/24), the country code (e.g. US), the registry (e.g. arin), the allocation date, and the API version.","failureModes":["Invalid IP address format returns an error","Invalid ASN format or non-existent ASN returns an error","Private or reserved IP ranges may return no results","Payment not processed results in HTTP 402 response","Network timeout or service unavailability returns a 5xx error"],"whenToPreferThis":"Use this endpoint when you need to identify the network owner, autonomous system, IP prefix, or registry details behind a specific IP address or ASN. Prefer this over generic IP geolocation APIs when the primary goal is ASN/network attribution rather than physical location coordinates. Ideal for network security investigations, abuse reporting, or enriching log data with ISP/operator context.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T18:35:44.326Z","isFirstParty":false}