ISPvsizWhich spelling fits?

Quick tell: ISP is a noun, iz is a verb, so they fill different roles in a sentence.

Which to use

“ISP” is a noun and “iz” is a verb - they look or sound alike but fill different roles in a sentence.

#20,971
“ISP” frequency rank
#32,457
“iz” frequency rank
53428
confusion score

Side-by-Side Comparison

Feature ISP iz
Definition Initialism of interstellar polarization. third-person singular simple present indicative of be

Letter map: ISP vs iz

Shared letters muted; letters that set ISP and iz apart highlighted. Shared run: 1.

3 ch
ISP
2 ch
iz

Grammar separator: ISP vs iz

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: ISP is anoun and izaverb. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 53428, derived from the frequency rank of both members and their visual similarity.

ISP is recorded at frequency rank #20,971, classified as anoun. iz is at rank #32,457, tagged as averb.

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 53428, this pair ranks #149,076 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of ISP vs iz

Shared letters: i. Private to "ISP": ps. Private to "iz": z.

"ISP" · 3 letters · shape VCC  ·  "iz" · 2 letters · shape VC

Frequently Asked Questions

Can "ISP" and "iz" be used interchangeably?
No - they are not even the same part of speech. "ISP" is a noun and "iz" a verb, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "ISP" or "iz"?
"ISP" is the more common of the two: it sits at frequency rank #20,971 in our English list, against #32,457 for "iz". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

You've compared "ISP" and "iz". Here's where to go from here.

  • Full dictionary entry for "ISP" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "iz" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #149,076 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "ISP" and "iz" also get mixed up with nearby pairs, the highest-scored neighbour is "ith vs iz". Nearby pair

Confusion rank #149,076 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list