At first sight, small change in your pocket can look very much the same, but have you ever really looked at the distinctions between UK coin sizes? Let’s talk about 1OZ GOLD BRITANNIA. Get a ruler and a hot drink. We’re going on an adventure to measure coins.

First, let’s get rid of the fog. The “1p,” or British penny, is not the biggest or the smallest. It is 20.3 mm long. Put a 2p coin next to it; it’s a lot thicker at 25.9mm. That was a big jump! These coins are funny when they stack up. If you put all of your coins in your hand, you might mix up the 2p and £2 coins. The £2 coin measures 28.4mm thick, which is surprising because it’s bigger than both the 1p and 2p coins.

The 5p is only 18mm long, yet it’s really powerful. If you blink, you’ll miss it at the bottom of your backpack. The 1p, which is the same size, seems heavier, but the 5p is the best at hiding between sofa cushions. That cunning, hard-to-find 20p with its seven-sided form is a different tale. It’s bigger than it looks at 21.4mm, but its strange shape can trick your sense of touch when you’re in a hurry.

We shouldn’t forget about the £1. Before 2017, the heavy, spherical pound with a 22.5mm diameter weighed down wallets everywhere. The dodecagonal design has twelve edges and is a little smaller, with a diameter of 23.43 mm. Edgy, in a real way. Some people still aren’t used to the new pound coin’s sharp edges.

The 50p coin is the one that is most likely to become trapped in vending machines. That coin is really strange; it measures 27.3mm. Its huge size and famous design make it easy to find even while you’re digging through a pile of pennies at the laundromat. The 10p, which is its cousin, is 24.5mm long and slimmer, making it easier to get out.

You’re not the only one who is having trouble with these figures. Collectors love the minor distinctions between old and new mintings. Some £5 coins that are meant to be kept as souvenirs are as big as 38.61mm. Good luck fitting that into your local parking meter!

Why are there so many different shapes and sizes? The short answer is that it’s easy to organize and find things, especially for people who can’t see well. Have you ever tried to pay for a drink in a dark bar? You’ll like the edges, ridges, and diameters more than ever. These different sizes also benefit coin sorting devices.

Speaking of trivia, things got even more complicated when the shilling, florin, and sixpence coins were around. Figuring out their diameters over time is a mix of arithmetic and detective work. If you ask a numismatist, they’ll know what I mean.

So the next time you hear change coming out of your wallet, take a few coins. Put them in a stack. Put them in a line. Size does matter when it comes to UK coins; each diameter tells a tiny narrative about British pocket change.