Check if a point is inside a rectangle

Compare the point with the rectangle’s edges.

JavaScript Version 1.0.0 · MIT · .md

function isInside({ point, rect }) { return point.x > rect.left && point.x < rect.right && point.y > rect.top && point.y < rect.bottom; }

Input & expected output

{
  "point": {
    "x": 5,
    "y": 5
  },
  "rect": {
    "left": 0,
    "top": 0,
    "right": 10,
    "bottom": 10
  }
}

true

The edge case

{
  "point": {
    "x": 10,
    "y": 5
  },
  "rect": {
    "left": 0,
    "top": 0,
    "right": 10,
    "bottom": 10
  }
}

false

Know the limits

• Points on an edge are outside, as the edge case shows.

The function above is the implementation used by the lab. The lab validates JSON types and caps size before execution; include equivalent validation when accepting untrusted input in your application.

Keep exploring

• Convert degrees to radians — Multiply by π and divide by 180.
• Check if a rectangle contains another one — Compare corners: a contains b when b’s corners sit inside or on a’s edges.
• Check if a rectangle overlaps another one — Two rectangles overlap when they overlap on both axes.