{"uid":"cap_xQ_4pJCDF3TeWqkTXM4Jl","slug":"fathom-macroeconomic-data-api-related-series-lookup-1a420936","name":"Fathom Macroeconomic Data API — Related Series Lookup","description":"Free macroeconomic data API powered by FRED. 816,000+ economic time series. GDP, inflation, unemployment, interest rates, and more.","url":"https://fredthom.vercel.app/api/related","method":"POST","headers":{},"bodySchema":{"type":"object","required":["seriesId"],"properties":{"seriesId":{"type":"string","description":"FRED series ID"}}},"responseSchema":{"type":"object","required":["source"],"properties":{"source":{"type":"string"},"series_id":{"type":"string"},"categories":{"type":"array","items":{"type":"object"}}}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.35","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":"$0.35/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.35","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.35","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_Lj5UsHXXug6z0cIFkCwyt","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.35","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns related FRED economic time series and their categories for a given FRED series ID","exampleAgentPrompt":"What FRED series are related to GDP (series ID 'GDP')? I want to discover other connected economic indicators and which categories they fall under.","exampleUseCases":null,"resultDescription":"Returns a JSON object with the source attribution (FRED), the queried series ID, and an array of related series objects including their categories — useful for navigating the FRED data graph and discovering related economic indicators.","failureModes":["Invalid or unknown FRED series ID returns empty or error response","Network timeout if FRED upstream is slow","Missing required seriesId field returns a validation error","Series ID with no related series returns empty categories array"],"whenToPreferThis":"Use this endpoint when you have a known FRED series ID and want to discover related or adjacent economic data series and their categories, enabling exploration of the FRED data graph. Prefer this over a general search when you already know the anchor series and want to branch out to related indicators.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T00:44:34.928Z","isFirstParty":false}