Perspective Grid Generator
Set your canvas size and horizon, choose 1-point or 2-point perspective, and get the vanishing-point coordinates plus the exact guide angle from any reference point on the page.
Grid geometry
The geometry behind the guide angle
Every straight edge that recedes into the distance in a perspective drawing points toward a vanishing point on the horizon. Once you know the pixel (or inch, or centimetre) coordinates of that vanishing point and the coordinates of a point on your drawing, the angle between them is just standard trigonometry — the arctangent of the vertical difference over the horizontal difference, computed with atan2 so it stays correct in every direction.
That angle is exactly what you'd measure with a protractor if you drew a line from your reference point straight to the vanishing point — this tool just does the arithmetic so you can rule the line confidently the first time.
Frequently Asked Questions
What's the difference between 1-point and 2-point perspective?
1-point perspective uses a single vanishing point directly on the horizon and works well for views looking straight down a road, hallway, or box face. 2-point perspective uses two vanishing points, one on each side of the horizon, and is the standard setup for drawing a box or building seen from a corner, where two sets of parallel edges recede in different directions.
Why do the vanishing points sit off the edge of the canvas?
In real perspective, vanishing points are often far outside the drawing itself — sometimes off the desk entirely. Placing them a set margin beyond each edge (rather than jammed against the border) keeps the convergence angles more gentle and realistic, which is closer to how a wide-angle scene actually recedes.
How do I use the guide angle this tool gives me?
Pick a point on your drawing — say, the near bottom corner of a box — and enter its coordinates as the reference point. The tool returns the exact angle (in degrees, measured from that point) that a receding edge toward each vanishing point should follow. Lay a ruler at that angle from your reference point and you have an accurate perspective line without eyeballing it.
Does the horizon line have to be centred?
No — the horizon represents eye level, and it moves depending on your viewpoint. A low horizon (closer to the bottom of the page) puts the viewer close to the ground looking up; a high horizon puts them above the scene looking down. Adjust the horizon percentage to match the vantage point you're drawing.
Educational tool only. Coordinates are in whatever unit you enter (pixels, inches, centimetres) — keep every field in the same unit for the angles to be meaningful.