{"uid":"cap_dUh_8vPmDY489KA3LvtJz","slug":"fastapi-online-luhn-algorithm-validator-e707fdc3","name":"fastapi.online Luhn Algorithm Validator","description":"Chat, embeddings, OCR, speech-to-text, image editing, image understanding (captioning/Q&A), text-to-speech, translation, writing tools, classification tools, developer tools, local utilities, format/checksum validators, encoding & crypto utilities, date/time calculators, geo/coordinate math, math & finance calculators, novelty tools, and business/social writing generators — 179 endpoints in all, across multiple specialized self-hosted models. Pay per call with crypto — no signup — or get an API key.","url":"https://api.fastapi.online/luhn-validate","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"number":{"type":"string","maxLength":40,"minLength":1}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.0005","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":"$0.0005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.0005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.0005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_gQunQ_LBJV0eSBOinudFT","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.0005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Validates a numeric string using the Luhn algorithm, typically used to verify credit card, IMEI, or other check-digit numbers","exampleAgentPrompt":"Can you run a Luhn check on the card number 4532015112830366 and tell me if it's valid?","exampleUseCases":[{"title":"Pre-payment card number check","prompt":"Before I submit this transaction, can you verify that the card number 4111111111111111 passes the Luhn algorithm so I know it's not obviously invalid?"},{"title":"IMEI number authenticity check","prompt":"I have an IMEI number 490154203237518 — can you run it through the Luhn validator to see if it's a legitimate format?"},{"title":"Bulk order form input sanity check","prompt":"A user just entered 1234567890123456 as their card number in our checkout form — can you Luhn-validate it before we even attempt to charge them?"}],"resultDescription":"Returns a validation result indicating whether the submitted numeric string passes the Luhn algorithm check — typically a boolean or pass/fail status indicating whether the check digit is correct.","failureModes":["Input contains non-numeric characters — rejected or fails validation","String too short or too long (outside 1–40 character bounds)","Empty string submitted — validation error returned","Network or payment gateway error if crypto micropayment fails","Ambiguous response if the API returns an error instead of a clean boolean"],"whenToPreferThis":"Choose this endpoint when you need a quick, cheap ($0.0005 USDC), no-signup Luhn checksum validation callable via a simple POST with no authentication setup. Ideal for agents or pipelines that need on-demand card/IMEI number pre-validation without integrating a full payment processing SDK or standing up local checksum logic.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T06:55:31.102Z","isFirstParty":false}