Ordinal Numbers
An ordinal number tells you the position of something (first, second, tenth). A cardinal number tells you how many (one, two, ten). Most ordinals add -th to the cardinal, with a few irregulars.
Rules
- Irregulars: first, second, third, fifth, eighth, ninth, twelfth — memorize these.
- Numbers ending in y: change the y to ie before adding th → twentieth, thirtieth, fortieth.
- Compound ordinals: only the last word takes the ordinal form → twenty-first, not twentieth-first.
- Use the short form (1st, 2nd, 22nd, 101st) for numerals, the written form in formal prose.
Examples
| Input | In words |
|---|---|
| 1 | 1st — first |
| 2 | 2nd — second |
| 3 | 3rd — third |
| 4 | 4th — fourth |
| 5 | 5th — fifth |
| 8 | 8th — eighth |
| 9 | 9th — ninth |
| 12 | 12th — twelfth |
| 20 | 20th — twentieth |
| 21 | 21st — twenty-first |
| 30 | 30th — thirtieth |
| 50 | 50th — fiftieth |
| 100 | 100th — one hundredth |
See also
- Spelling Money Amounts
Learn how to write dollar and cent amounts in words for US checks, contracts, and legal documents — with rules for 'and 00/100 dollars' and examples from $1 to $1,000,000. - Writing Numbers on a Check
Step-by-step guide to writing numbers in words on a US bank check, including cents as NN/100, where to place 'and', and real check-writing examples. - Writing Dates in Words
How to write dates and years like 'April 23, 2026' or 'July 4, 1776' in full English words for wedding invitations, diplomas, and legal contracts. - Saying Phone Numbers in Words
Learn how to pronounce and spell out US phone numbers, area codes, and toll-free 1-800 numbers digit by digit in English. - Spelling Fractions
Learn how to spell fractions in English words by combining a cardinal numerator with an ordinal denominator — plus when to hyphenate fractions. - Spelling Decimal Numbers
How to read and write decimal numbers like 3.14, 0.5, and 0.005 in English words — both digit-by-digit after 'point' and by tenths/hundredths. - Spelling Negative Numbers
Learn how to write and pronounce negative numbers like -1, -47, and -100 in English using 'negative' for math/finance and 'minus' for temperatures. - Million, Billion, Trillion, and Beyond
Learn the short-scale names and spellings for large numbers in English — million, billion, trillion, quadrillion, quintillion, and how to chunk 3-digit groups.