{"uid":"cap_i4J-56qaDHXBrK5cc1N_h","slug":"geo-calc-geodesic-inverse-vincenty-wgs84-distance-bearings-3338d6d9","name":"Geo Calc – Geodesic Inverse (Vincenty/WGS84 Distance & Bearings)","description":"Ellipsoidal (WGS84, Vincenty) distance and bearings between two points, compared with haversine on a sphere.","url":"https://geo-calc.x402tookit.com/geodesic-inverse?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":["lat1","lon1","lat2","lon2"],"properties":{"lat1":{"type":"number","description":"Start latitude"},"lat2":{"type":"number","description":"End latitude"},"lon1":{"type":"number","description":"Start longitude"},"lon2":{"type":"number","description":"End longitude"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","properties":{"asOf":{"type":["null","string"]},"miles":{"type":["null","number"]},"source":{"type":["null","string"]},"reasons":{"type":["array","null"],"items":{"type":"string"}},"summary":{"type":["null","string"]},"verdict":{"type":["null","string"]},"degraded":{"type":["boolean","null"]},"converged":{"type":["boolean","null"]},"ellipsoid":{"type":["null","string"]},"disclaimer":{"type":["null","string"]},"iterations":{"type":["null","number"]},"kilometers":{"type":["null","number"]},"notChecked":{"type":["array","null"],"items":{"type":"string"}},"nauticalMiles":{"type":["null","number"]},"initialCompass":{"type":["null","string"]},"finalBearingDeg":{"type":["null","number"]},"initialBearingDeg":{"type":["null","number"]},"haversineDistanceM":{"type":["null","number"]},"ellipsoidalDistanceM":{"type":["null","number"]},"haversineInitialBearingDeg":{"type":["null","number"]},"haversineMinusEllipsoidalM":{"type":["null","number"]}}}}}}},"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_ZTXBihGW3dJpI9W460A0d","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":"Computes the ellipsoidal (WGS84 Vincenty) distance and forward/reverse bearings between two lat/lon points, alongside a haversine sphere comparison.","exampleAgentPrompt":"What is the precise WGS84 ellipsoidal distance and initial bearing from New York (40.7128, -74.0060) to London (51.5074, -0.1278)? Give me kilometers, miles, and the Vincenty vs haversine comparison.","exampleUseCases":[{"title":"Flight path distance verification","prompt":"Can you calculate the exact geodesic distance between Los Angeles (34.0522, -118.2437) and Tokyo (35.6762, 139.6503) using the WGS84 ellipsoid? I need it in kilometers and nautical miles along with the initial compass heading."},{"title":"Precision land survey distance check","prompt":"I need the Vincenty ellipsoidal distance between these two survey points: 51.4778° N, 0.0015° W and 48.8584° N, 2.2945° E — show me how much it differs from the haversine approximation too."},{"title":"Drone navigation bearing computation","prompt":"What's the initial and final bearing between my drone's starting position at 37.7749, -122.4194 and its target at 37.3382, -121.8863? I also need the distance in meters so I can program the flight path."}],"resultDescription":"Returns the ellipsoidal (Vincenty/WGS84) distance in meters, kilometers, miles, and nautical miles; the initial and final bearing in decimal degrees plus a human-readable compass direction; the haversine spherical distance in meters and its initial bearing; the difference between haversine and ellipsoidal results; the ellipsoid name used; whether Vincenty's iterative algorithm converged; iteration count; and optional disclaimer text.","failureModes":["Vincenty algorithm may not converge for nearly-antipodal points (converged=false returned with degraded flag)","Invalid lat/lon values outside [-90,90] / [-180,180] cause a 400 error","Identical start and end coordinates return zero distance and undefined bearing","Missing required query parameters (lat1, lon1, lat2, lon2) result in a 400 validation error","Payment not received or x402 authorization failure returns 402 Payment Required"],"whenToPreferThis":"Choose this endpoint when you need high-accuracy geodesic distance (Vincenty WGS84) rather than a simple great-circle haversine approximation — particularly for long-distance paths, precision navigation, surveying, or when the difference between spherical and ellipsoidal models is significant. It is ideal when you also need both initial and final azimuths (bearings) and want the haversine comparison included in the same response. If you only need polygon area, use the area sibling; for destination point from bearing+distance, use the direct problem sibling.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-29T13:15:02.256Z","isFirstParty":false,"canonicalSlug":"geo-calc-geodesic-inverse-vincenty-wgs84-distance-bearings-3338d6d9"}