Numbers in Korean

The counting of objects to convey an amount to others is a natural occurrence in communication.

And naturally in language numbers are a necessary feature. It’s no coincidence the natural numbers in maths refers to the numbers used in counting. So, without making further thought, one would assume there not be many differences between languages either.

Yet, some languages do differs in its grammar on how to count, and how to treat multiples of things. The number systems in Korean and Japanese are an example: both of these languages have in fact two sets of numbers used for counting.

And one is not some historical remains that just exist in text books for remembrances' sake. In conversesarion both systems are commonly used alongside another, switching depending on what is being counted. Yes, in Korean, when stating the time, the hour is counted with one kind of number, and the minutes with the other.

Numbers in Korean

The words noted in the tables below are written in Hangeul (한글, the Korean script). It’s a well designed writing system for Korean, and fortunately, it’s relatively quick to pick up the ability to read it. With some effort it can be learnt in a day.

Though I’ll include transcription in the text following; learning to read the script is essential to learn the language.

Two seperate number systems

The Korean language uses two seperate sets of numerals to express numbers.

The first number system is natively Korean in origin, and for that reason they are referred to as Korean numerals in grammar books. The second set of numbers has its roots in the Chinese language, and are called Sino-Korean numerals.

Starting from one to ten

The following table summerises the numbers from 1 to 10. in the two number systems of the Korean language.

These numbers are the key to form larger numbers. For example, to say 11 we can combine the numerals for 10 and 1: yeol-hana (열하나), or si-bil (십일), and to say 12 we can instead of 1 say 2: yeol-du (열두), or si-bi (십이).

Besides the fact that we deal with two systems, this does not differ much to the method of counting in English. Indeed, have a look at the following table for the numbers up to 20.

There is only a peculiarity at 20. Since we run out of digits, we must find another way to keep counting. And that is how, at this point, the differences between the two number systems become apparent.

In the Korean number system, a different word altogether is used to say 20: seu-mul (스물) – just like English, it is “twenty.” After things, we can keep counting until we run out of digits again. Once we hit another multiple of 10, we must use another new word.

The Sino-Korean numbers forms the number 20 systematically saying i-sip (이십), which literally means “two ten.” This way, using just the numbers 1-10, we can work our way up to 99: gu-sip gu (구십 구).

Ten fold

Let’s now look at multipels of ten–compare the two number systems.

There’s a blank you say? Nope – the native Korean numbers in fact not extend beyond 100, and lack ordinals higher than a hundred. Counting higher than a hundred in Korean means using Sino-Korean numbers.

This was not always the case: these natively Korean numbers do exist, but they have fallen out of favour and are no longer commonly used.

In the Sino-Korean way, numbers are always expressed systematically, and thus so easily expresses to large numbers without being clogged up by notation or different ordinal words. It is very much relies on functionally decomposing a number, just like is done is scientific notation.

For foreign language learners, this is arguably the reason why it is the easiest number system to learn, and to become fluent in counting in.

Base 10000

To count higher, we hence use the Sino-Korean number system, which is almost algorithmically easy to expand: we just need more higher-order ordinals.

Just like in English, we have a word for ten hundreds: a thousand; and then to keep counting higher a word for a thousand thousands: a million.

Indeed, we already know how to say a hundred in Korean, so we need a word for a thousand, that’s cheon (천).

However, there is one odd addition: there is in fact also a word for a hundred hundreds. The Sino-Korean numbers include the separate words man (만) for the number 10.000, and ak (악) for 10.000 times 10.000.

This also means that there is no special word for a million: it is a hundred ten thousands: baek man (백만).

Keep going, even higher

The number 10.000 effectively takes on the same role as 1.000 in English: it is the base. We need a new word for every power of 1.000 to keep counting higher in English.

The words to express large numbers in English thus are: one million is 1.000.000, and one billion is 1.000.000.000. To keep scaling up, we add three zeroes and change increase the prefix by one.

And rebase

The Sino-Korean numbers have a base of scale that is different than the English one: it is larger by a factor of 10. This is important to remember when dealing with nubmers in Korean and English.

To convert from English, we have to re-factorise in groups of 10'000. Thus twenty thousand (20'000) becomes i-man (이만), and a hundred thousand (100,000) becomes sip man (십만).

The population of London (9,425,622) nine million four hundred twenty five thousand six hundred and twenty two, is instead gu-cheon sa-baek i-sip o-man yuk-baek i-sip i (구천 사백 이십 오만 육백 이십 이). And the population of South Korea (51,315,955) or fifty one million three hundred fifteen thousang nine hundred fifty five is o-cheon il-baek sam-sip il man o-cheon gu-baek o-sip o (오천 일백 삼십 일 만 오천 구백 오십 오).