$salons = Salon::select('salons.*')
    ->selectRaw('( 6371* acos( cos( radians(?) ) *
                   cos( radians( lat ) )
                   * cos( radians( lng ) - radians(?)
                   ) + sin( radians(?) ) *
                   sin( radians( lat ) ) )
                 ) AS distance', [$lat, $lng, $lat])
    ->havingRaw("distance < 25")
    ->where("category_Id" , "=" , $id)
    ->get();

esta consulta me da esto-

"distance": 0.05205731665026305, I want distance like this 1.2KM

intento pero no encontré la solución