{"uid":"cap_xWv42b3Jj1AiXGgxKOA33","slug":"lookproof-cidr-subnet-splitter-0ac2fe15","name":"Lookproof CIDR Subnet Splitter","description":"Check SPF, DMARC, DKIM, MTA-STS, DNSSEC and more, with results that explain what was found and why. Free browser checks and a pay-per-request API with x402.","url":"https://api.lookproof.dev/v1/ip/subnets?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","HEAD","DELETE"],"type":"string"},"queryParams":{"type":"object","title":"SubnetsInput","required":["cidr","prefix"],"properties":{"cidr":{"type":"string","title":"Cidr","maxLength":64,"minLength":2},"prefix":{"type":"integer","title":"Prefix","maximum":128,"minimum":0}},"additionalProperties":false}},"additionalProperties":false}}},"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_iggOos1IE0HwW4LiAywH7","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":"Splits an IPv4 or IPv6 CIDR block into equal subnets of a specified longer prefix, returning up to 256 subnets in order","exampleAgentPrompt":"Split 192.0.2.0/24 into /26 subnets and list them all for me so I can plan which blocks to assign to each team.","exampleUseCases":[{"title":"Cloud VPC subnet allocation planning","prompt":"I need to divide 10.0.0.0/16 into /24 subnets so I can assign one to each availability zone — can you enumerate them in order?"},{"title":"Data center IPv6 delegation layout","prompt":"We have a 2001:db8::/48 block and need to hand out /56 prefixes to our tenants — list the first 256 subnets for me."},{"title":"Network team address handout","prompt":"Break 172.16.0.0/20 into /28 subnets and give me the ordered list so I know what to assign to each department."}],"resultDescription":"An ordered list of up to 256 subnets derived from the input CIDR block, each expressed at the requested longer prefix length. Requests that would produce more than 256 subnets are rejected before any computation occurs. The response is computed offline without external DNS or routing lookups.","failureModes":["Requested split produces more than 256 subnets — refused with an error before any computation","Prefix length shorter than or equal to the CIDR prefix (no subdivision possible)","Prefix length out of range (e.g. >32 for IPv4 or >128 for IPv6)","Malformed CIDR notation in the cidr parameter","Mismatched IP version between CIDR and prefix length"],"whenToPreferThis":"Use this endpoint when an agent needs to enumerate subnets within a CIDR block for IP address planning, infrastructure layout, or subnet assignment tasks. It runs offline and is deterministic, making it ideal for planning workflows. It caps output at 256 subnets, so it is best suited for moderate splits; if a finer split is needed, restructure the request into smaller parent blocks first.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-31T18:40:11.524Z","isFirstParty":false,"canonicalSlug":"lookproof-cidr-subnet-splitter-0ac2fe15"}