IMDbvsIRBWhich spelling fits?

Quick tell: IMDb is a name, IRB is a noun, so they fill different roles in a sentence.

Which to use

“IMDb” is a name and “IRB” is a noun - they look or sound alike but fill different roles in a sentence.

#21,544
“IMDb” frequency rank
#33,690
“IRB” frequency rank
55234
confusion score

Side-by-Side Comparison

Feature IMDb IRB
Definition Initialism of Internet Movie Database, a website that documents movies and television shows. Initialism of institutional review board, a committee that reviews the designs of proposed experiments to confirm whether all the methods proposed are ethical.

Letter map: IMDb vs IRB

Shared letters muted; letters that set IMDb and IRB apart highlighted. Shared run: 2.

4 ch
IMDb
3 ch
IRB

Role in the sentence - IMDb and IRB

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: IMDb is aname and IRBanoun. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 55234, derived from the frequency rank of both members and their visual similarity.

IMDb is recorded at frequency rank #21,544, classified as aname. IRB is at rank #33,690, tagged as anoun.

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 55234, this pair ranks #135,131 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of IMDb vs IRB

Shared letters: bi. Private to "IMDb": dm. Private to "IRB": r.

"IMDb" · 4 letters · shape VCCC  ·  "IRB" · 3 letters · shape VCC

Known mistypes of this pair

  • IMDbidmb · imbd · imdbb · imddb · immdb · midb

Frequently Asked Questions

Can "IMDb" and "IRB" be used interchangeably?
No - they are not even the same part of speech. "IMDb" is a name and "IRB" a noun, so a sentence built for one is usually ungrammatical with the other.
In ordinary English text, does "IMDb" or "IRB" show up more?
"IMDb" is the more common of the two: it sits at frequency rank #21,544 in our English list, against #33,690 for "IRB". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

Done with this confusable. These links stay specific to "IMDb" and "IRB".

  • Full dictionary entry for "IMDb" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "IRB" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #135,131 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "IMDb" and "IRB" also get mixed up with nearby pairs, the highest-scored neighbour is "IRB vs ith". Nearby pair
  • Recorded mistypes exist for at least one side of this pair, useful when a spell-checker or OCR lands on the wrong form. See mistypes

Confusion rank #135,131 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