Ordinal Numbers 1-30

One, two, three … are cardinal numbers.
First, second, third … are ordinal numbers.

You can normally create ordinal numbers by adding -TH to the end of a cardinal number.

• Four – Fourth
• Sixteen – Sixteenth

The main exceptions are with the numbers 1, 2, and 3.

• one – first
• two – second
• three – third

Also you need to be careful with the spelling of some ordinal numbers:

• five – fifth (not “fiveth“)
• nine – ninth (not “nineth“)

List of Ordinal Numbers from 1st-31st

Ordinal numbers are normally used for:

Dates

• Her birthday is on the 29th. (Twenty-ninth)
• Halloween is on the 31st of October. (thirty-first of October)

Learn how to write dates in English

Writing dates in English

Position

• I’m the fifth and Anita is the first.

Floors of a building

• The toy department is on the third floor.

Source: https://www.woodwardenglish.com/lesson/ordinal-numbers-in-english/