turf.area gives incorrect result

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I’m trying to find the area of the same polygon, via Turf and PostGIS. I Get varying outputs from both.

Turf gives: 2822907.8214477254 while PostGIS gives 2816602.27320234 for spherical area

[Scoppio]

Turfjs Area is wrong to the point that it is actively causing harm in multiple applications where I work and we are having to delegate area calculation to other libraries. The area calculation seems very close to the result given by projecting to ESRI 54009, but still, the precision fluctuates alot.

[dylel]

I needed this area calculation to be the same as QGIS/MSQL/POSTGRES for work so I’ve tried a bunch of things and eventually found this post:

Post About Postgres

Which references this library geographiclib-js.

Appears to be written by the author referenced in the code ( Charles Karney) to this article/document article

So temporarily i’m using this

// similar to turf, summing up rings (i.e. multipolygons)
// this may not be necessary if the geographic polygon can support multipolygons
function polygonArea(coords: number[][][][]) {
  let total = 0;
  if (coords && coords.length > 0) {
    for (let i = 0; i < coords.length; i++) {
      const area = geographicLibArea(coords[i][0]);
      total += area;
    }
  }
  return total;
}

const geographicLibArea = (coordinates: Array<Coord>) => {
// the geodesic format of my lat, lng coordinates
// you can specify your own if you have the appropriate constants
  const geod = GeographicLib.Geodesic.WGS84;


// build polygon in geographic
  let poly = geod.Polygon(false);
  for (let i = 0; i < coordinates.length; ++i) {
    poly.AddPoint(coordinates[i][1], coordinates[i][0]);
  }

  poly = poly.Compute(false, true);

  return Math.abs(poly.area.toFixed(0));
};

Docs can be found here: GeographicLib Js Docs

It would be great if we could get the formula derivatives implemented in turf. I’ve followed several algorithms before (shoelace, gauss, vincenty) but having a bit of trouble with the referenced document in terms of the formulas actually needed to get this done.