About the Ordinal Number Converter
Ordinal numbers show position or order: first, second, third and so on. In figures they take the endings st, nd, rd or th, which follow rules that are easy to get wrong, especially for 11, 12 and 13. This converter takes whole numbers, one per line, and gives you the ordinal in figures, the ordinal in words and the plain number in words. It works for numbers up to 999 trillion, handles negative numbers and thousands separators, and keeps the list in the order you entered it.
Updated October 2026
How to use the Ordinal Number Converter
- 1Type or paste your numbers, one per line.
- 2Read the ordinal in figures, such as 22nd.
- 3Read the ordinal in words, such as twenty-second.
- 4Read the number in words, such as twenty-two.
- 5Copy the converted list.
Ordinals in everyday writing
Ordinals appear in dates, rankings, floors of a building, anniversaries and centuries. We say the 21st century, the 3rd floor and a 50th birthday. In legal and formal documents, words are often preferred for small numbers, such as the fifth day of the month, while figures are used in tables and lists.
Words and figures are used for different purposes. News style often writes ordinals below ten in words, such as the third time, and uses figures from 10 up, such as the 21st century. Dates in letters may use either 3 March or 3rd March. Sports tables, floor numbers and rankings are nearly always in figures. When you are writing for a certificate, an invitation or a legal document, the spelled-out form is often preferred, and this converter gives you both versions, so you can pick the one your style guide requires.
Ordinals are also useful in programming and design. A calendar widget, a ranking list or a leaderboard might need to turn a position number into text such as 1st or 22nd, and the rules here can be copied into code. The exception for 11, 12 and 13 is the one that trips up most simple scripts, which usually look only at the last digit and so produce 11st by mistake.
Quick patterns
- 1st, 21st, 31st, 101st, but 11th and 111th.
- 2nd, 22nd, 32nd, 102nd, but 12th and 112th.
- 3rd, 23rd, 33rd, 103rd, but 13th and 113th.
- All other numbers end in th, including 0th and 20th.
- Fractions use ordinals too: one third, three quarters.
Related tools
The Number to Words tool writes amounts and cheque values in words, the Roman Numeral Converter turns numbers into Roman numerals, the Number Base Converter switches between binary and hex, and the Week Number Calculator tells you which week of the year a date falls in.
Features
- Ordinals in figures and in words
- Cardinal number in words
- Lists of up to 200 numbers
- Handles 11th, 12th and 13th correctly
- Negative numbers and commas
- Offline friendly
Frequently asked questions
What are the rules for st, nd, rd and th?
Numbers ending in 1 take st, 2 take nd, 3 take rd and everything else takes th. The exception is the teens: 11, 12 and 13 always take th, as in 11th, 12th and 13th, and the same holds for 111th, 112th and 113th.
How do you write ordinal numbers in words?
Most just add th to the cardinal word: seven becomes seventh. Some change: one is first, two is second, three is third, five is fifth, eight is eighth, nine is ninth and twelve is twelfth. Numbers ending in y change to ieth, like twentieth.
How do I write 21st in words?
Twenty-first, with a hyphen between the tens and the units. Only the last word becomes an ordinal, so 101st is one hundred first and 1,000th is one thousandth.
Should I use superscript for the endings?
In formal writing and many style guides the endings are written at normal size, such as 3rd. Superscript is common in word processors and older styles, but it is not necessary in plain text.
Can it do dates like 3rd of March?
The ordinal part works for the day number. Convert 3 to 3rd and write the month yourself. Style guides differ on whether to write 3rd March, March 3 or March 3rd.
What is the largest number it can convert?
999,999,999,999,999, just under 1 quadrillion, which is as far as numbers can be handled exactly. Use a smaller number or split the task for anything larger.