20 cm equals 7.87 inches.
That’s the short answer.
Round it up and you’ve got roughly 8 inches, which is about the length of a dollar bill turned sideways, or the width of a standard sheet of paper.
But numbers on a screen don’t always click.
You want to feel how long 20 cm actually is, without digging out a tape measure.
So here’s the plan.
First, you’ll get every unit conversion you could possibly need.
Then, we’ll walk through 12 everyday objects that are almost exactly 20 cm, so you’ve got a mental ruler for life.
And if you’ve ever wondered why a “20 cm pizza” looks smaller on your plate than it sounds on the menu, stick around. That part surprises most people.
20 CM By Every Unit You Could Ever Need
Let’s get the metric to imperial conversion out of the way first, since that’s usually what sends people searching in the first place.
20 centimeters converts to 7.874 inches, 0.656 feet, 0.219 yards, and 200 millimeters. In meters, it’s simply 0.2 m, a fifth of a full meter stick.
Here’s a quick reference table you can bookmark:
| Unit | Value |
| Millimeters | 200 mm |
| Centimeters | 20 cm |
| Inches | 7.87 in |
| Feet | 0.66 ft |
| Yards | 0.22 yd |
| Meters | 0.2 m |
Why does the inch figure look so oddly specific? Because the imperial system and the metric system were never designed to line up neatly. One meter equals 39.37 inches, and centimeters are just a hundredth slice of that. So when you convert small metric lengths, you rarely land on a clean whole number.
A handy trick: multiply centimeters by 0.39 to get a fast, close-enough inch estimate. It won’t be lab-precise, but it’s perfect for quick mental math at the hardware store or while packing a suitcase.
Twelve Things Near You Right Now That Prove the Point
Numbers are fine, but your brain remembers objects better than digits.
Here are 12 things that hover right around 20 cm, so you can eyeball this length measurement anywhere, anytime.
Some of these you’ll have within arm’s reach today.
1. A Folded Newspaper (Half Page Width)
Fold a standard broadsheet newspaper in half, and the width you’re left with lands close to 20 cm.
Next time you pick one up at a café, measure it against your palm. You’ll notice it’s just a touch wider than most adult hands. That gap is roughly your 20 cm benchmark.
2. A Standard Unsharpened HB Pencil
A brand-new, unsharpened HB pencil measures almost exactly 19 to 20 cm from tip to eraser.
This is genuinely one of the easiest ways to remember the size. Keep one on your desk, and you’ve basically got a built-in ruler you never have to think about.
3. A Men’s Dress Shoe (Size 8 UK / 42 EU)
A men’s dress shoe in size 8 UK, or 42 EU, runs about 20 cm from heel to toe.
Shoe sizing charts actually use centimeter-based foot length as their backbone, which is why shoe stores in Europe often just ask for your foot length in cm instead of a size number.
4. A Paperback Novel (Width)
Grab any standard paperback off your shelf. The width, not the height, typically sits around 19.8 cm.
Publishers stick to this size for a reason. It fits comfortably in one hand and slides into a bag without fuss, which is a small design detail most readers never notice but always benefit from.
5. A Wooden Cooking Spoon
A classic wooden cooking spoon, the kind that’s been in kitchens for generations, usually measures close to 20 cm.
If you’ve got one hanging near your stove right now, that’s your reference point sorted. Simple, reliable, and already in your kitchen drawer.
6. A Tablet Screen Diagonal (Small Compact Tablets)
Smaller, compact tablets often have a screen diagonal near 20 cm, which translates to roughly 7.9 inches.
That’s smaller than a standard iPad but noticeably bigger than a phone. It’s the sweet spot for reading e-books or watching a quick video without the bulk of a full-size tablet.
7. A Standard Envelope (DL Size)
A DL envelope, the long, slim one used for formal letters and invoices, measures 22 cm by 11 cm. The longer edge sits just above our 20 cm mark, close enough to use as a visual anchor.
Next time a bill lands in your mailbox, glance at its length. You’re looking at almost exactly our target size.
8. A Newborn Baby’s Foot
Here’s one that surprises people: a newborn baby, from heel to the top of the head measured in certain growth chart contexts, isn’t what we mean here. Instead, think of a toddler’s shoe insert or a baby blanket fold, both of which frequently measure near 20 cm in width.
It’s a strangely comforting size reference, isn’t it? Something this small, and it’s still roughly the length of a pencil.
9. A Craft Beer Can (Tall 500ml Format)
Tall format craft beer cans, the 500ml size you’ll see at breweries and bottle shops, stand around 16.8 cm, with the taller specialty cans stretching closer to 19 to 20 cm depending on the brand.
Next time you’re holding one, notice how it compares to your pencil or your dress shoe. Same rough length, completely different object.
10. A Personal Pizza (20 cm Pizza Size)
A personal pizza sized at 20 cm across is one of the most searched comparisons for this exact measurement, and for good reason. It sounds bigger on a menu than it looks on your plate.
We’ll dig into why that happens in a section below, because there’s a math trick restaurants rely on that most customers never clock.
11. A Hardback Children’s Book
Picture books and hardback children’s books are often printed at close to 20 cm in height, sometimes a touch more.
Publishers size these deliberately so small hands can hold them easily, while still leaving enough page space for bold illustrations.
12. A Standard House Brick (Length)
A standard UK house brick measures 21.5 cm in length, just a hair over our 20 cm mark, making it one of the closest real-world matches on this entire list.
If you’ve got a garden wall or a fireplace nearby, that’s your reference right there, already built into your house.
Left Your Ruler Somewhere? Try These Instead
Not every situation gives you a tape measure. So here’s how to estimate 20 cm using things you probably already have on you.
A standard credit card is 8.56 cm long, so line up just over two of them end to end. Most smartphones, held vertically, run close to 15 cm, meaning you’d need one phone plus roughly a third more to hit 20 cm.
Your own hand works too. Spread your fingers wide, thumb to pinky. For most adults, that span lands somewhere between 18 and 22 cm. It’s not exact, but it’s close enough for quick, real-world estimates when precision doesn’t matter.
The 20 cm Pizza Angle Most People Miss
Here’s the part almost nobody talks about.
A 20 cm pizza sounds like a solid, filling meal on a menu. But pizza size is measured by diameter, and area grows by the square of that number, not in a straight line.
So a 20 cm pizza has roughly half the surface area of a 28 cm pizza, even though the diameter only looks a bit smaller. That’s why a “personal pizza” this size can leave you reaching for a second one, while the difference in listed size felt minor.
Next time you’re comparing pizza sizes, don’t just look at the centimeter number. Do a rough area comparison first, or you might end up ordering less food than you expected.
Why Small Metric Conversions Trip People Up
Most confusion around 20 cm doesn’t come from the math. It comes from not having a reference point.
You can memorize that 1 inch equals 2.54 cm all day long, but until you connect it to a pencil, a shoe, or a brick, the number stays abstract. That’s really the whole point of this list. It turns a unit conversion into something you can picture without opening a calculator.
This matters especially when you’re shopping online. A product listing might say “20 cm width” with no photo for scale, and suddenly you’re guessing whether it’ll fit your shelf or your suitcase. Keep two or three of the objects above in your memory, and you’ll never be caught guessing again.
Quick Reference You Can Save
If you only remember one thing from this article, make it this: 20 cm sits between the length of a pencil and the length of a dress shoe.
That single mental image covers most everyday situations, whether you’re checking if a gift box will fit in a drawer or figuring out if a phone case is the right size before you buy it.
FAQs
Is 20 cm the same as 8 inches?
Not exactly. 20 cm equals 7.87 inches, which rounds to about 8 inches for casual, everyday use.
What household item is closest to 20 cm?
An unsharpened HB pencil and a standard house brick are two of the closest matches, both landing within a centimeter of the mark.
How many millimeters are in 20 cm?
200 millimeters, since each centimeter equals 10 millimeters.
Is a 20 cm pizza enough for one person?
It depends on appetite, but because pizza size scales by area rather than diameter, a 20 cm pizza is noticeably smaller than it sounds. Many people order a side dish alongside it.
How do I measure 20 cm without a ruler?
Use two credit cards laid end to end, or spread your hand from thumb to pinky, which for most adults comes close to this length.
