I'svsIVWhat's the difference?

Quick tell: I's is a noun, IV is an adjective, so they fill different roles in a sentence.

Which to use

“I's” is a noun and “IV” is an adjective - they look or sound alike but fill different roles in a sentence.

#25,096
“I's” frequency rank
#3,762
“IV” frequency rank
28858
confusion score

Side-by-Side Comparison

Feature I's IV
Definition plural of I (letter of the alphabet or the ego) Abbreviation of intravenous.

Where the spellings diverge

Shared letters are muted; the letters that actually set I's and IV apart are highlighted. They share 1 letter in sequence, which is exactly why the eye skips the difference.

3 ch
I's
2 ch
IV

Spelling & Dictionary Insight

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: I's is anoun and IVanadjective. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 28858, derived from the frequency rank of both members and their visual similarity.

I's is recorded at frequency rank #25,096, classified as anoun. IV is at rank #3,762, tagged as anadj, pronounced /ˌaɪ ˈviː/.

Glosses for this pair are partially populated in our dataset, but the full side-by-side definitions above should still guide you to the right choice.

With a confusion score of 28858, this pair ranks #367,728 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of I's vs IV

Shared letters: i. Private to "I's": s. Private to "IV": v.

"I's" · 2 letters · shape VC  ·  "IV" · 2 letters · shape VC

Frequency comparison

I's#25,096
IV#3,762

Source: FrequencyWords open word-frequency list

Frequently Asked Questions

Can "I's" and "IV" be used interchangeably?
No - they are not even the same part of speech. "I's" is a noun and "IV" an adjective, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "I's" or "IV"?
"IV" is the more common of the two: it sits at frequency rank #3,762 in our English list, against #25,096 for "I's". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Remembering I's vs IV

The fastest way to pick the right one every time.

  • Check the role first: if you need a noun, it's “I's”; for an adjective, it's “IV”.
  • See each word in full, definition, IPA, etymology and its other confusables. Full “I's” entry
  • Browse more pairs most likely to be confused. Most confusable

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list