About

Geometry you can actually see

Draw to Scale is a growing set of free geometry calculators. Every one of them does the same thing: takes the few measurements you already have, works out everything you don't, and shows the result as a proper, dimensioned drawing — not just a column of numbers.

Why "drawn to scale"

Most online calculators hand you an answer and stop there. You get a number for the area, or the missing angle, and you're left to picture the shape yourself. That's fine until the shape is the part you're unsure about — and it's exactly where mistakes creep in.

So this site does it the other way around. Type in what you know, and the shape is drawn in front of you, true to scale, with each side and angle labelled. The labels aren't decoration: click any value on the drawing and you can change it, and everything re-solves around your edit. It turns each tool into something closer to a quick sketch than a form.

Who's behind it

Made by an old-school drafter on the Gold Coast in Queensland, Australia — and I mean pen-and-ink old school. I've spent a long time reading and producing technical drawings for a living, back when a shape, a dimension and an angle had to be right the first time, and legible at a glance, because there was no undo button. Draw to Scale grew out of that habit: the conviction that a good drawing explains a calculation better than the calculation explains itself.

The tools are built and checked by hand, one shape at a time. The maths under each one is the same trigonometry and geometry you'd do on paper — just done instantly, and drawn for you.

What's here, and what's coming

Right now you can solve triangles, right triangles, circles, sectors, ellipses, rectangles and squares, trapezoids, regular polygons, parallelograms and annuli — plus a full volume section covering fifteen 3D solids, from cubes and cylinders to pipes, tori and spherical caps, each drawn as an editable isometric figure on a blueprint sheet. More tools are always on the way, and each follows the same idea: one job, done well, drawn to scale.

Got a suggestion, found a shape that's missing, or spotted something that looks off? I'd like to hear it.