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Ninety one or Ninety-one?

Ninety one or ninety-one?

In this article we show you how to write 91 in English words correctly.

In addition, we provide you with the grammar rule right away. 🙂

Regardless of where they appear in a number, hyphenate all compound numbers between 21 and 99 (not 30, 40, 50, 60, 70, 80, and 90) such as 91. In other words:

Hyphenate all numbers between twenty-one and ninety-nine, except those divisible by ten, even if the compound number is preceded or succeeded by numbers that do not require hyphens.
Thus, the correct spelling of 91 is ninety-one (hyphenated).

Along the same lines:
  • 91,000 = ninety-one thousand (hyphenated).
  • 91,000,000 = ninety-one million (hyphenated).
  • 91,000,000,000 = ninety-one billion (hyphenated).

Ninety-one or Ninety one Spelling

It doesn’t matter which noun follows the adjective, the grammar rule explained above remains in place.

In the examples below the correct spelling is underlined.

Ninety one years or ninety-one years?
Ninety one percent or ninety-one percent?
Ninety one hours or ninety-one hours?

Frequently Asked Questions about Ninety One

Does ninety one have a hyphen?

Yes, 91 has a hyphen and is spelled correctly as ninety-one.

Do you hyphenate ninety one?

Yes, you put a hyphen between ninety and one: ninety-one.

Does ninety one need a hyphen?

As 91 is a compound number in between 21 and 99 it needs a hyphen; therefore writing 91 in full is ninety-one.

In the table below we show you the correct spelling of some numbers succeeding and precededing 91:

Ninety first or Ninety-first?

In the following examples the correct spelling is underlined.

Ninety first part or ninety-first part?
Ninety first day or ninety-first day?
Ninety first hour or ninety-first hour?

Frequently Asked Questions about Ninety first

  • Does ninety first have a hyphen? Yes, the ordinal number for 91 has a hyphen and is spelled correctly as ninety-first.
  • Do you hyphenate ninety first? Yes, you put a hyphen between ninety and first: ninety-first.
  • Does ninety first need a hyphen? 91 is a compound number in between 21 and 99 which needs a hyphen. Thus, writing 91st in full is ninety-first.

Ninety first or Ninety-one?

As you already know, 91 as cardinal numeral is ninety-one, and 91 as ordinal numeral is ninety-first.

Thus, the question in the subtitle above mixes two distinguished linguistic concepts and cannot be answered as such.

Observe that you can always check how to spell a number in full correctly using our converter below.





Letter case:

Sentence case
Title Case
Spelling: Ninety-one


As explained by the hyphens-in-numbers rule, 91 = ninety-one.

If you are happy with our information, then you may also be interested in our article ninety-three or ninety three.

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– Article written by Mark