This API expects as input legacy mulipoint geojson with the crs of the input defined as "crs" and the output defined as the "target_crs".

Allowed values for crs.type: "EPSG" and "name"

Allowed values for crs.properties: "code" if crs.type="EPSG" and "name" if crs.type="name"

Allowed values for crs.properties.code: "4258" and "28992"

Allowed values for crs.properties.name: "etrs89" and "rdnap"

Example json string:

            {
                "type": "Multipoint",
                "crs": {
                    "type": "EPSG",
                    "properties": {
                        "code": "28992"
                    }
                },
                "target_crs": {
                    "type": "name",
                    "properties": {
                        "name": "etrs89",
                        "coordinate_order": [
                            1,
                            0
                        ]
                    }
                },
                "coordinates": [
                    [
                        155000,
                        463000,
                        0
                    ],
                    [
                        90000,
                        400000,
                         53

                    ]
                ]
            }
        

Posting this, for example with curl,

curl -d '{"type": "Multipoint", "crs": {"type": "EPSG","properties": {"code": "28992"}}, "target_crs": {"type": "name","properties": {"name": "etrs89","coordinate_order": [1,0]}}, "coordinates": [[155000,463000,0],[90000,400000,53]]}' -H "Content-Type: application/json" -X POST https://geopinie.nl/transform/api

will return a simlar json string.

        {
            "type": "Multipoint",
            "crs": {
                "type": "name",
                "properties": {
                    "name": "etrs89",
                    "coordinate_order": [
                        1,
                        0
                    ]
                }
            },
            "source_crs": {
                "type": "EPSG",
                "properties": {
                    "code": "28992"
                }
            },
            "transformation_applied": "RDNAPTRANS2018",
            "coordinates": [
                [
                    52.155172888,
                    5.387203649,
                    43.2772
                ],
                [
                    51.585149983,
                    4.44932115,
                    97.111
                ]
            ]
        }