Rhumb-line distance & bearing API

Computes the loxodrome (rhumb line) between two points: distance, the single constant compass bearing you steer the whole way, and how much longer it is than the great circle. Answers 'What constant heading connects two points?', 'How much extra distance does a rhumb line add?'.

Price$0.04per request

MethodPOST

Route/v1/geo/rhumb-line

StatusLive

MIME typeapplication/json

Rate limit120/minute

Cache0s public

geogisrhumb-lineloxodromeconstant-bearingnavigationdistancemercatorheading

API URLhttps://x402.hexl.dev/v1/geo/rhumb-line

Integration docs

Example request

{
  "from": {
    "latitude": 51.5074,
    "longitude": -0.1278
  },
  "to": {
    "latitude": 48.8566,
    "longitude": 2.3522
  }
}

Example response

{
  "from": {
    "latitude": 51.5074,
    "longitude": -0.1278
  },
  "to": {
    "latitude": 48.8566,
    "longitude": 2.3522
  },
  "distanceKm": 343.572362,
  "distanceMiles": 213.485902,
  "distanceNauticalMiles": 185.514234,
  "constantBearing": 149.083291,
  "greatCircleKm": 343.556535,
  "extraDistanceKm": 0.015827,
  "interpretation": "Rhumb line: 343.572 km on a constant heading of 149.083°, 0.016 km longer than the 343.557 km great circle. Easier to steer; longer to travel."
}

Input schema

{
  "type": "object",
  "required": [
    "from",
    "to"
  ],
  "properties": {
    "from": {
      "type": "object",
      "required": [
        "latitude",
        "longitude"
      ],
      "properties": {
        "latitude": {
          "type": "number"
        },
        "longitude": {
          "type": "number"
        }
      },
      "examples": [
        {
          "latitude": 51.5074,
          "longitude": -0.1278
        }
      ]
    },
    "to": {
      "type": "object",
      "required": [
        "latitude",
        "longitude"
      ],
      "properties": {
        "latitude": {
          "type": "number"
        },
        "longitude": {
          "type": "number"
        }
      },
      "examples": [
        {
          "latitude": 48.8566,
          "longitude": 2.3522
        }
      ]
    }
  }
}

Output schema

{
  "type": "object",
  "additionalProperties": true
}