Spelling out numbers can be tricky. Learn how to write 30 in words correctly with examples and tips in this comprehensive guide! Learn how to write numbers from 1 to 30 in words with rules and examples. Download a printable chart of number names 1 to 30 and practice with online math classes. 30 in Words: Here’s how to spell the number, along with all relevant information, a converter and examples including 30th. Rule 2: For numbers 1-20, 30 , 40, 50, 60, 70, 80, 90, 100, and 1000, we can directly refer to the number names 1 to 40 chart to write their spellings. For example, the number name of 5 is Five, the number name of 14 is Fourteen, the number name of 30 is Thirty, and so on.