{"uid":"cap_Na-IidqCcYPRkOlw4mhOp","slug":"geo-calc-polygon-area-perimeter-centroid-83f3d363","name":"Geo Calc – Polygon Area, Perimeter & Centroid","description":"Area, perimeter and centroid of a lat,lon polygon using spherical excess on the WGS84 equal-area sphere.","url":"https://geo-calc.x402tookit.com/polygon-area?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"],"type":"string"},"queryParams":{"type":"object","required":["points"],"properties":{"points":{"type":"string","description":"Vertices as lat,lon;lat,lon;... (3 to 300, ring may or may not repeat the first point)"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","properties":{"asOf":{"type":["null","string"]},"valid":{"type":["boolean","null"]},"areaM2":{"type":["null","number"]},"method":{"type":["null","string"]},"source":{"type":["null","string"]},"areaKm2":{"type":["null","number"]},"reasons":{"type":["array","null"],"items":{"type":"string"}},"summary":{"type":["null","string"]},"verdict":{"type":["null","string"]},"degraded":{"type":["boolean","null"]},"vertices":{"type":["null","number"]},"areaAcres":{"type":["null","number"]},"disclaimer":{"type":["null","string"]},"notChecked":{"type":["array","null"],"items":{"type":"string"}},"perimeterM":{"type":["null","number"]},"centroidLat":{"type":["null","number"]},"centroidLon":{"type":["null","number"]},"orientation":{"type":["null","string"]},"perimeterKm":{"type":["null","number"]},"areaHectares":{"type":["null","number"]},"selfIntersecting":{"type":["boolean","null"]}}}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.02","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":"$0.02/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_1eTvuUz1KyjA_OARVtCeU","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.02","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Calculates the area (m², km², hectares, acres), perimeter (m, km), centroid (lat/lon), and orientation of a lat/lon polygon using spherical excess on the WGS84 equal-area sphere.","exampleAgentPrompt":"Can you calculate the area, perimeter, and centroid of this field? The boundary vertices are: 51.5074,-0.1278;51.5080,-0.1265;51.5065,-0.1255;51.5058,-0.1270","exampleUseCases":[{"title":"Measure farmland parcel area","prompt":"I have a field mapped out with GPS — here are the boundary points: 53.2001,-1.5432;53.2010,-1.5415;53.1995,-1.5400;53.1982,-1.5418;53.1988,-1.5440. Can you calculate its area in hectares and acres, and tell me the perimeter?"},{"title":"Find centroid of a zoning district","prompt":"I need the geographic center of a zoning polygon defined by these lat/lon vertices: 40.7128,-74.0060;40.7135,-74.0045;40.7120,-74.0030;40.7110,-74.0050. What's the centroid and total area in square kilometers?"},{"title":"Validate property boundary polygon","prompt":"Can you check if this property boundary polygon is valid and self-intersecting, and give me its area in m²? Vertices: 34.0522,-118.2437;34.0530,-118.2420;34.0515,-118.2410;34.0505,-118.2428"}],"resultDescription":"Returns a JSON object with area in m², km², hectares, and acres; perimeter in metres and km; centroid latitude and longitude; vertex count; polygon orientation (clockwise/counterclockwise); self-intersection flag; computation method; validity flag with reasons; and optional disclaimer/summary fields.","failureModes":["Fewer than 3 vertices provided — returns invalid/error response","Malformed points string (wrong delimiter, missing values) — parse error or 400 response","More than 300 vertices submitted — rejected with validation error","Self-intersecting polygon detected — flagged in response but may still return degraded results","Antipodal or polar-spanning polygons may yield inaccurate spherical excess results","Payment not included or insufficient — x402 payment required error"],"whenToPreferThis":"Choose this endpoint when you need accurate geodetic area, perimeter, and centroid calculations for a polygon on the WGS84 ellipsoid — particularly for land parcels, geographic boundaries, or GIS workflows requiring multi-unit output (m², km², hectares, acres) in a single call. Prefer this over flat-earth or simple Euclidean calculators when precision over curved Earth surfaces matters. Also useful when you need self-intersection validation or polygon orientation alongside the geometric measurements.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-29T13:12:39.063Z","isFirstParty":false,"canonicalSlug":"geo-calc-polygon-area-perimeter-centroid-83f3d363"}