Latin Numbers: How To Count & Talk About Numbers In Latin

When learning Latin, it won't be long before you come into contact with and need to understand how to use Latin numbers.

Numbers can be intimidating when learning a language due to the aspects that make each number system unique.

Many languages, like Latin, have cardinal and ordinal numbers, as well as numerals and spelled-out numbers.

This article will help you quickly become an expert with the nuances of the counting system of the Romans, no matter the intricacy. 

Latin Cardinal Numbers 

Cardinal numbers are numbers that are used to count items. For example, in English “one fish, two fish” the “one” and “two” are examples of cardinal numbers. For the most part, cardinal numbers are adjectives.

Unlike typical Latin adjectives, not all cardinal numbers in Latin will decline according to gender, number, and case (see my post on Latin grammar for more about this).

Latin numbers one through three as well as hundreds above one hundred, such as two hundred and four hundred, will decline.

The remaining cardinal numbers don't decline, meaning the form will remain the same no matter the noun they are modifying.

See the chart below to see the cardinal numbers 1 – 20, as well as the tens up to 100.

1	unus, a, um	21	viginti unus OR unus et viginti
2	duo, duae, duo	30	triginta
3	tres, tres, tria	40	quadraginta
4	quattuor	50	quinquaginta
5	quinque	60	sexaginta
6	sex	70	septuaginta
7	septem	80	octoginta
8	octo	90	nonaginta
9	novem	100	centum
10	decem	101	centum et unus, a, um
11	undecim	200	ducenti, ae, a
12	duodecim	300	trecenti, ae, a
13	tredecim	400	quadrigenti, ae, a
14	quattuordecim	500	quingenti, ae, a
15	quindecim	600	sescenti, ae, a
16	sedecim	700	septingenti, ae, a
17	septendecim	800	octingenti, ae, a
18	octodecim OR duodeviginti	900	nongenti, ae, a
19	novendecim OR undeviginti	1,000	mille
20	viginti	1,001	mille et unus, a, um

Saying The Tens With Latin Cardinal Numbers

Over twenty, any number between the tens, such as 20 and 30, is the tens number plus the number above the tens number.

For example, thirty-five in Latin is triginta quinque. Triginta, meaning 30, plus quinque, meaning 5, which gives you thirty-five. An alternative of writing this would quinque et triginta, meaning five and thirty, or thirty-five.

Latin Ordinal Numbers 

Ordinal numbers are used to rank or order things.

For example, if deciding the place of a race, in English you would use “first, second, third” and following.

In Latin, all of the ordinal numbers are declined according to the gender, number, and case of the noun that it is modifying. 

1st	primus, a, um	21th	vicensimus, a, um primus OR unus, a, um, et vicensimus, a, um
2nd	secundus, a, um	30th	tricensimus, a, um
3rd	tertius, a, um	40th	quadragensimus, a, um
4th	quartus, a, um	50th	quinquagensimus, a, um
5th	quintus, a, um	60th	sexagensimus, a, um
6th	sextus, a, um	70th	septuagensimus, a, um
7th	septimus, a, um	80th	octogensimus, a, um
8th	octavus, a, um	90th	nonagensimus, a, um
9th	nonus, a, um	100th	centensimus, a, um
10th	decimus, a, um	101st	centensimus, a, um primus, a, um
11th	undecimus, a, um	200th	ducentensimus, a, um
12th	duodecimus, a, um	300th	trecentensimus, a, um
13th	tertius, a, um decimus, a, um	400th	quadringentensimus, a, um
14th	quartus, a, um decimus, a, um	500th	quingentensimus, a, um
15th	quintus, a, um decimus, a, um	600th	sescentensimus, a, um
16th	sextus, a, um decimus, a, um	700th	septingentensimus, a, um
17th	septimus, a, um decimus, a, um	800th	octingentensimus, a, um
18th	octavius, a, um decimus, a, um OR duodevicensimus, a, um	900th	nongentensimus, a, um
19th	nonus, a, um decimus, a, um OR undevicensimus, a, um	1,000th	millensimus, a, um
20th	vicensimus, a, um	1,001	millensimus, a, um primus, a, um

Saying The Tens With Latin Ordinal Numbers

Much like the cardinal numbers, ordinal numbers above twentieth are written with the tens number with the number above the tens value.

For example, fifty eighth in Latin will be written as fiftieth eighth, or quinquagensimus, a, um octavus, a, um. It can also be written as eighth and fiftieth, or octavus, a, um et quinquagensimus, a, um. 

Roman Numerals 

Roman numerals aren't as straightforward as cardinal and ordinal Latin numbers. You'll see Roman numerals less frequently in literature.

Instead, Roman numerals are often seen in inscriptions because, for the most part, they take up less space than numbers.

Most languages today utilise Arabic numerals, such as 1, 2, 3, etc. Roman numerals utilise certain letters organised in particular orders. 

See the chart of the basic letters used for numerals and their value. 

I	1
V	5
X	10
L	50
C	100
D	500
M	1,000

The system of Roman numerals is based on the addition and subtraction of the values. When a letter of equal or greater value is placed before another numeral, you would add the values together.

See the chart below for examples:

III	1 + 1 + 1 = 3
XV	10 + 5 = 15
CLX	100 + 50 + 10 = 160
MMM	1,000 + 1,000 + 1,000 = 3,000

Addition And Subtraction Of Roman Numerals

When a letter of lesser value is placed before another numeral, you would subtract the value. Once the number begins to be larger, it's best to begin to group letters until you see a circumstance where you need to begin subtracting.

See the chart below for examples.

IX	10 – 1 = 9
XL	50 – 10 = 40
DCCC	500 + 100 + 100 + 100 = 800
CM	1,000 – 100 = 900
CDIV	(500 – 100) + (5 – 1) = 404
MMXIX	(1,000 + 1,000) + [10 + (10 – 1)] = 2019

Once the numbers get larger, Roman numerals can be unwieldy. It's important to remember that once you encounter a letter that increases in value from one letter to the next, that indicates you need to do some subtraction before continuing on.

Using brackets like in math will be helpful to start understanding how to put these numerals together. 

Latin Numbers In Dates And Names

One place that you will often see numbers, now and in the past, are in dates. The Ancient Roman Calendar is significantly different from most modern calendars.

Rather than counting from the first day of the month, the Roman calendar counts based on the distance before and after three different day markers: the kalends, nones, and ides.

The kalends is the first day of the month; nones is the 5th day of the month in all months except March, May, July, and October in which it is the 7th day; and the ides is the 13th day of the month in all months except March, May, July, and October in which it is the 15th day. 

The day of the month is determined based on which marker date it is leading up to. If the date is the 6th of January, the kalends and nones have already passed. The 6th will then be measured based on the number of days before the ides of January.

This would be written as “the eighth day before the January ides,” or ante diem viii ides Ianuarias. If the date is after the ides, such as July 18th, it would be written as “the 14th day before the August kalends,” or ante diem xiv kalendas Augustas.

Some university diplomas are written in Latin. Fortunately, they don't use the Ancient Roman calendar based on the kalends, nones, and ides. Instead, they use the modern calendar of using the number of days past the first day of the month.

For the modern-day calendar, the date would be written as “the (cardinal number) day of the month of (name of month), (year).” For example, to say “May 4th, 1998” it would be written as diem quattuor mensis Maii MCMXCVIII.

Roman Names

Commonly, ordinal numbers are used in Roman names.

Roman women were often named based on the order of their birth, such as Aemilia Tertia, indicating that this daughter is the third daughter born to this family.

Men also may have a cardinal number in their name to indicate the rank in the birth of sons. Typically Primus, Prima, Secunda, and Secundus aren't as common, especially if there are only two sons or daughters, choosing instead to label them as Major or Minor depending on which is oldest. 

FAQs About Latin Numbers

Latin Numbers & How To Count In Latin

There are several things to keep in mind when learning Latin numbers. First, there are differences between cardinal and ordinal numbers. Are you counting things or are you putting them in a specific order or ranking?

Second, beyond numbers being written out, you will also see Latin numbers written in Roman numerals. These have their own specific, and slightly more complicated, system of numbering. 

Learning to count in Latin is important for numerous reasons. For general counting purposes, it's important to understand what you're reading or for writing to get across more information.

Knowing Latin ordinal numbers can also be important for recognising certain names of men and women and learning more about their family structure. 

You'll certainly make some mistakes when learning these counting conventions, but once you get it nailed down you will easily recognise all types of Latin numbers.

So for now, to make mastering Latin numbers easy, apply the rules of StoryLearning® and read Latin books. As you read, you'll see the numbers in action and you'll internalise and start using them more easily.