Have you ever written “13rd” and paused, unsure if it’s right? You’re not alone. Ordinal numbers in English can be confusing, especially when similar ones like 3rd exist.
Let’s make it simple so you never get it wrong again.
Quick Answer
“13th” is correct.
“13rd” is incorrect and should not be used.
✔ Correct: Today is the 13th of the month.
❌ Incorrect: Today is the 13rd of the month.
What Does “13th” Mean
“13th” is an ordinal number that means:
- The position number after 12th
- Something that comes in the thirteenth place
Examples of “13th”
- My birthday is on the 13th.
- He finished in 13th place.
- The meeting is scheduled for the 13th.
- She lives on the 13th floor.
Why “13rd” Is Wrong
“13rd” is a mistake caused by confusion with numbers like:
- 3rd
- 23rd
- 33rd
But numbers ending in 11, 12, and 13 follow a special rule.
The Rule for Ordinal Numbers
Use:
- 1st → 1st
- 2nd → 2nd
- 3rd → 3rd
- 4th and beyond → th
Important Exception
Numbers ending in 11, 12, 13 always use “th”, not st, nd, or rd.
✔ 11th
✔ 12th
✔ 13th
13rd vs 13th Comparison
| Feature | 13rd | 13th |
|---|---|---|
| Correct form | ❌ No | ✔ Yes |
| Rule followed | No | Yes |
| Usage | Incorrect | Standard English |
| Example | 13rd day ❌ | 13th day ✔ |
Common Mistakes to Avoid
1. Following the last digit only
❌ 13rd (because of “3”)
✔ 13th (exception rule)
2. Forgetting special cases
Always remember 11, 12, 13 use “th.”
3. Guessing based on similar numbers
Not all numbers follow the same pattern.
Easy Trick to Remember
👉 Think: 11, 12, 13 are special → always “th”
Or:
👉 “Teen numbers break the rule” → use th
American vs British English
There is no difference:
- “13th” is correct in both American and British English
- “13rd” is incorrect everywhere
Practice Questions
Choose the correct form:
- Today is the ___.
✔ 13th - He came in ___ place.
✔ 13th - The event is on the ___.
✔ 13th
FAQs
1. Is “13rd” ever correct
No, it is always a mistake.
2. Why is it “13th” not “13rd”
Because numbers ending in 11, 12, and 13 always use “th.”
3. What is the rule for ordinal numbers
Most follow last digit rules, except 11, 12, 13.
4. Is this a common mistake
Yes, many people confuse it with “3rd.”
5. Is “13th” used in formal writing
Yes, it is standard everywhere.
6. How can I remember it easily
Think: 11–13 always use “th”
Summary
The difference between 13rd vs 13th is simple. “13th” is correct, while “13rd” is a common mistake. The correct form follows the special rule for numbers ending in 11, 12, and 13.
Using the correct form improves your writing accuracy and clarity.
Actionable Takeaway
Next time you write the number, remember:
👉 Always use 13th
👉 Never use 13rd
👉 Remember the 11–13 rule
A quick check can help you avoid this common error easily.
