permvsperpWhich spelling fits?

Which to use

“perm” and “perp” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#24,863
“perm” frequency rank
#44,400
“perp” frequency rank
69263
confusion score

Side-by-Side Comparison

Feature perm perp
Definition Clipping of permanent wave (“hairstyle”). A perpetrator.

Where the eye mixes perm and perp

Muted = shared; highlighted = the visual trap. They share 3 letters in sequence.

4 ch
perm
4 ch
perp

Look-alike desk: perm vs perp

A purely visual mix-up. perm (/pɝm/) and perp (/pɝp/) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they differ by a single letter - m in “perm” becomes p in “perp”. Our composite confusion score for this pair is 69263, derived from the frequency rank of both members and their visual similarity.

perm is recorded at frequency rank #24,863, classified as anoun, pronounced /pɝm/. perp is at rank #44,400, tagged as anoun, pronounced /pɝp/.

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 69263, this pair ranks #55,334 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of perm vs perp

Shared letters: epr. Private to "perm": m. Private to "perp": -.

"perm" · 4 letters · shape CVCC  ·  "perp" · 4 letters · shape CVCC

Known mistypes of this pair

  • permeprm · pemr · permm · perrm · pperm
  • perpeprp · pepr · perpp · perrp · pperp

Frequently Asked Questions

Is swapping "perm" for "perp" ever safe?
No. They are said differently (/pɝm/ versus /pɝp/) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Which is more common, "perm" or "perp"?
"perm" is the more common of the two: it sits at frequency rank #24,863 in our English list, against #44,400 for "perp". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.

  • Full dictionary entry for "perm" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "perp" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #55,334 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "perm" and "perp" also get mixed up with nearby pairs, the highest-scored neighbour is "pecs vs perp". 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 #55,334 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