Correct spelling

23rd

Correct spelling, explanation: 23rd is the correct way to write this ordinal number, due to the fast, that in the word form it’s twenty-third, so it ends with the same letters as numeral form. At the same time th ending is used for most, but not all ordinal numbers, for example, 7th (seventh), or 109th (one hundred ninth). This is why 23rd is correct and 23th is incorrect.

Definition of 23rd:
numeral, the ordinal number between 22nd and 24th
– How old is she? – It was her 23rd birthday yesterday.
This cup is the 23rd in my cups-from-around-the-world collection.


Incorrect spelling

23th

Incorrect spelling, explanation: we don’t add -th ending to ordinal number twenty-third in numeral form, because it should end with the same sound as the word, so in this case with rd. See the pattern:
twenty-third23rd
twenty-fourth – 24th
twenty-second – 22nd
etc.
Hence 23th is incorrect and 23rd is the correct form.

Incorrect spelling

23nd

Incorrect spelling

Incorrect spelling

23st

Incorrect spelling