Tip for drawing perfect circles
Published by Manning on July 1st, 2016
A lot of my projects call for drawing various circles to cut out of foam board or poster board. If the exact size isn’t important, I just trace a plate or a bowl or whatever. But sometimes I need a circle to be a precise size, so this is the trick I always use.
I just grab a small rectangular scrap of foam board (or cardboard or poster board) and draw a line on it with a ruler, marking off 0″ and half the size of the circle I want (i.e. the radius of the circle). For this example, I want to make a 10″ circle, so I’ve marked off 5″ on the foam board.
Then I poke a hole in both points with an awl (of course you can use a toothpick, a nail, a sharp pencil, etc). Then I lay this shape onto a big piece of foam board, hold it in place at the 0″ mark with the awl, and put a pen through the 5″ hole, and spin the thing around to draw the 10″ circle. Easy!
(One nice thing about this technique is you already have the exact center of the circle marked. Sometimes that’s important for whatever project you’re doing with the circle. If you start by tracing a plate, it’s really hard to find the exact center from there.)
Of course you can also use a compass for drawing circles, but I actually find that to be much harder to do nicely; there’s something awkward about the twisting motion and having to keep the tip of the pen steady on the paper all the way around. My method is way easier, you can make way bigger circles than with a compass, and I actually think it’s much more accurate than a compass when you’re trying to get a very specific sized circle.
Enjoy!
About Manning Krull
How to make a 4-foot paper maché alligator
My violin skull mask, Mardi Gras 2015
Three-headed paper maché dragon sculpture
July 3rd, 2025 at 3:26 am
This DIY compass method is genius! I love how you can get exact measurements and mark the center at the same time. I totally agree that regular compasses can be awkward to use smoothly. Your foam board technique seems so much more stable. After reading this, I’m curious to test my circle-drawing skills at https://perfect-circle.fun – it’s a fun little game that judges how perfectly round your circles are. Would be interesting to see how different techniques compare!
September 19th, 2025 at 1:54 am
Tips for drawing circles. You can try it out here, and you’ll figure it out. I recommend a particularly interesting game, which is much more fun than drawing circles. Let me briefly introduce it.
queens game is a modern and sophisticated web-based logic puzzle that reinvents the classic N-Queens problem. It’s not merely a clone of a traditional game but a complete reimagining, designed to offer a deeper, more engaging strategic experience for puzzle enthusiasts worldwide. The project’s philosophy is to merge elegant, minimalist design with complex, thought-provoking challenges, creating a purely skill-based and highly rewarding brain-teaser.