What Are Ordinal Numbers? Chart from 1st to 20th and Examples for Kids

Ordinal numbers show the place or position an item holds within an ordered series, for example first, second, third, fourth. They are usually written with a suffix attached to the digit (1st, 2nd, 3rd) or spelled out as a full word. Unlike cardinal numbers, which count how many items there are (3 apples, 10 pencils), ordinals answer the question “in what place?” rather than “how many?” Kids run into them every day: the first day of school, the second row in the classroom, the third floor of a building or fourth place in a race. Learning to use them helps children organize information, follow step-by-step instructions and understand sequences in time, a skill that matters both in math and in everyday life.

The difference lies in what each one represents. A cardinal number counts an amount: there are 5 chairs, the team scored 3 goals, I am 10 years old. An ordinal number shows a position within an order: she finished fifth in the race, this is the third time he has tried, he lives on the tenth floor. A simple way to tell them apart with a child is to ask two different questions: “how many are there?” gets a cardinal answer (there are 8 runners), while “what place did she finish in?” gets an ordinal answer (she finished fourth). A good way to practice is counting objects with cardinals, then lining them up and naming each one's position with ordinals, like the second book in the pile or the first toy in the box.

From 1st to 10th, English ordinals are: first (1st), second (2nd), third (3rd), fourth (4th), fifth (5th), sixth (6th), seventh (7th), eighth (8th), ninth (9th) and tenth (10th). Most of them are formed by adding “-th” to the cardinal number, but the first three are irregular and worth memorizing on their own: one becomes first, two becomes second, three becomes third. A couple of spelling changes are easy to miss: five drops the “e” before adding “th” (fifth), and nine also drops its final “e” (ninth). These first ten ordinals are the foundation for every ordinal that comes after them, including the ones past the twentieth.

Ordinal numbers teach kids to organize information in order, a skill they use constantly without noticing it: following step-by-step instructions (“first, second, third”), understanding the order of months or days of the week, lining up, or making sense of results in a competition. They show up from the earliest grades, both in math and in early literacy, because ordering events in time (what happened first, what happened next) is part of understanding a story or a process. They are also the foundation for more advanced concepts, like fractions, which depend on understanding position and division into parts. Practicing ordinals in everyday contexts, like games or family routines, makes the learning stick better than memorizing a list of words.

Ordinal numbers are usually introduced in the early years of elementary school, generally between ages 5 and 7, alongside cardinal numbers and basic counting. At first, kids only work with 1st through 10th using concrete examples, like lining up or taking turns in a game, and later the range expands to 20th and eventually 100th as they get comfortable writing larger numbers. In later grades, ordinals come back when studying dates, book chapters, sports rankings or instructions with numbered steps. It is not a topic taught once and forgotten: it gets reinforced over several years because it shows up naturally in daily life and in other subjects, not just math.