Why are the Numbers on a Dartboard in That Order?

The game of darts is very popular, and can be enjoyed by basically anyone, whether at your local pub, a competitive tournament, or just in the comfort of your own home. All you need to play is a nice dartboard and a good set of darts, both of which are relatively inexpensive for the hours of fun that they provide.

However, to a complete beginner player darts can seem like a confusing and difficult game to understand, and a lot of that confusion comes from the seeming randomly ordered numbers around the edge of the dartboard. 

The reason for why the numbers on a dartboard are in that specific order is at the same time both complicated and pretty simple. Let’s first look at what the exact order is and then discuss how it came to be and why it works.

The Face of a Dartboard

A dartboard is divided up into 20 radial sections that all have the exact same dimensions and area. These sections are like thin triangles that have a curved outer edge, and they all converge to a point in the middle of the dartboard. These sections usually alternate black and white in order to more easily see the difference between neighboring ones.

Bullseye

In the middle of the board is the bullseye. The bullseye part is further segmented into the inner bullseye – the very middle circle, which is usually red – and the outer bullseye, which is the doughnut shaped ring around the inner bullseye and is usually colored green. 

Single, Double, and Treble (Triple) Areas

Each of the 20 radial segments on the dartboard are either colored mainly black or white. However, there are also red and green sections in between these black and white portions. This is to differentiate between the amount of points you can get with each dart throw. 

The black and white portion of each dartboard segment is called the single area. If you land a dart in one of these areas, it is worth the face value of the number that the radial segment corresponds to. For example, landing a dart in the single area of the number 15 gets you 15 points.

The outermost ring, which alternates between red and green in each section so that you can more easily tell the neighboring segments apart, is called the double area. Darts that land in this area are worth double points, so a 15 doubled would be 30 points.

The inner doughnut ring – not the outer bullseye, but the ring that separates the single area into two portions – is called the treble area, or triple area. Darts landing here are worth triple the amount of points, so a treble 15 would be 45 points. 

How are the Numbers Arranged on a Dartboard?

All of the 20 radial sections of the dartboard have a corresponding number to them, so therefore there are 20 numbers written around the outer ring of the board. 

These numbers are in a seemingly random order. Starting from the very top number (the 20) and going clockwise around the dartboard gives us this numbering order: 

20 – 1 – 18 – 4 – 13 – 6 – 10 – 15 – 2 – 17 – 3 – 19 – 7 – 16 – 8 – 11 – 14 – 9 – 12 – 5

As you can see, the numbers appear to bounce around between high and low numbers. There is no pattern that immediately jumps out, like ascending or descending numbers next to each other, or even alternating between the highest and lowest numbers. For example, the 19 and the 20 are 9 sections away from each other, but the 20 and 18 are only 2 away.

History of the Numbering System

Dartboards were not always numbered in this way. Before the twentieth century, all the way back to medieval times, dartboards were often not numbered at all. Starting in the 1800s, there were a bunch of differing number patterns used in different parts of England and France. 

It wasn’t until 1896 that the numbering system you see above was introduced, and since then it has been widely adapted and used as the standard for all dartboards.

Who is Brian Gamlin? 

Brian Gamlin was a carpenter that lived in Lancashire, England. As a carpenter, one of the products he made and sold were wooden dartboards, made from elm or poplar or oak. 

Gamlin is credited with creating the number system still used today in 1896 and writing the numbers on his dartboards that he sold.

In England at the time, there was a law against gambling, and the game of darts was caught up in these circumstances. Judges and lawmakers were unsure whether or not it was a game of chance or a game of skill. 

Gamlin sought to create a distinction between those who have a lot of skill at darts and those who don’t, so he ordered the numbers in a specific way that would most accurately reflect the skill of the player – good players would do well and bad players would do poorly. With this change, the game was then seen as a game of skill rather than chance, and it was allowed in pubs and homes because it was not considered gambling. 

Thomas William Buckle

Brian Gamlin is not the only person credited with coming up with the specific order of numbers seen on the border of all modern dartboards. A man named Thomas William Buckle, Yorkshire, England is also said to have invented the number system in 1913. He was a wire maker and worker, who supposedly took a dartboard with 5 sections, increased the number of sections to 20, and changed the order of the numbers to go with it. 

Regardless of who actually created the numbering system, the important part is that it is still in use today and has been found to be as nearly perfect of an option as someone could come up with. But why is it a good order, and why does it work so well?

Why is the Numbers Sequence as it is?

When the number sequence was established back in the late 19th or early 20th century, the game of darts needed to prove that it was a game of skill rather than a game of luck. This sequence ended up being the best way to show that, and to regularly determine that better players would win games against worse players. 

There are many ways to order the numbers around a dartboard. In fact, there is an astronomically large number of ways to order them. With 20 sections to work with, you can arrange the numbers 1-20 in 2.43 x1018 different ways. 

Written out, that would be 2,432,902,008,176,640,000, which is over 2 quintillion. That number is on the same order of magnitude as the total number of grains of sand on earth. Needless to say, there were a lot of options to choose from when numbering the dartboard. So why choose this one? 

Put Adjacent Numbers Far Apart

The first accomplishment the current numbering order achieves is that it spreads out a player’s throws around the dartboard. Because getting as many points as possible in the fewest throws is the objective of the game, people would aim at the highest numbers the vast majority of the time – the 17, 18, 19, and 20 segments. 

By spreading these segments into different places on the dartboard, it makes players throw to many different locations, and to increase their skill level to do so. If they were all next to each other, one could use muscle memory to aim at the same spot every time, but as they’re spread out, players have to practice many different shots.

Eliminate Lucky Shots

The second, and more important, aspect of the number sequence is it greatly reduces the amount of luck a player can have. By placing high point sections and low point sections next to each other, you are more highly penalized for missing your target throw. 

For example, the 20 and 18 sections, toward the top right of the board, are neighbored by the 1, 4, and 5 sections, and the 19 and 17 have the 2, 3, and 7 sections next to them. Say you aim for the 20 segment – a good player will hit the 20, or even double or treble 20, and get a lot of points. However, a player with less skill might hit one of the two sections on either side – the 1 or the 5 – and end up with significantly fewer points.

This sequence therefore eliminates the luck of aiming for one high number and landing on another – or at least significantly reduces it. It also makes it so that the more skilled player can beat the lower skilled player almost every time, defining darts as a game of skill. 

The Mathematically Optimal Dartboard

Many mathematicians have researched the dartboard numbering order to see how it can be changed for the better. Is it possible to make a dartboard that is more effective at reducing luck and putting adjacent numbers as far apart as possible?

David F. Percy, the University of Salford, published a journal article in Mathematics Today in December of 2012, describing a new numbering sequence that could replace the current one.

The order of Percy’s dartboard numbering series is structured to have two additional constraints: 

  • The numbers are placed odd-even-odd-even. 
  • Numbers of similar value are dispersed as uniformly as possible throughout the board.

The new number sequence would therefore look like this, still starting with the 20 at the top of the board and moving clockwise from there: 

20 – 1 – 18 – 5 – 14 – 9 – 10 – 13 – 6 – 17 – 2 – 19 – 4 – 15 – 8 – 11 – 12 – 7 – 16 – 3

What Difference Would This New Number Sequence Make?

This latest dartboard, according to Percy, would make the most significant difference at the end of a game where the rules require a player to finish on the double. For example, say a player has an odd number of points, and therefore needs to hit an odd number so they can then hit a double to win (because doubles are, by definition, always even numbers).

On the current dartboard, there is a group of numbers at the bottom of the board that go: 7 – 19 – 3 – 17. Even an unskilled player in this situation could hit one of those four, because aiming for the middle would likely result in hitting at least one of them. However, with the extra stipulation that Percy added with alternating evens and odds, this becomes a lot more difficult. 

Additionally, the most common number to double out with is the 16, because if you miss and hit a single 16 you can then double out on the 8, and missing that then the 4, then the 2, and so on. With the current number order, the 16 and the 8 are right next to each other, making that final throw easier to practice and to hit in the game. 

The new proposed sequence has the 16 and the 8 four segments away from each other, with the 16 surrounded by the 3 and the 7, so it is more difficult to finish the game if you miss your first double out.

Conclusion

The order of the numbers on the dartboard is a very unique feature of the game of darts. It was invented a long time ago, and has worked very well for millions of professional and amateur dart players since then. We hope this article was able to shed some light on how the numbers on the edge of the dartboard work, and why they are set up that way, and that you can take this knowledge and improve your darts game!