CPUvscruxWhich spelling fits?

Which to use

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

#10,835
“CPU” frequency rank
#27,109
“crux” frequency rank
37944
confusion score

Side-by-Side Comparison

Feature CPU crux
Definition Initialism of central processing unit. The basic, central, or essential point or feature.

Where the eye mixes CPU and crux

Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.

3 ch
CPU
4 ch
crux

Why the eye confuses CPU with crux

A purely visual mix-up. CPU (/(ˌ)siː(ˌ)piːˈjuː/) and crux (/kɹʌks/) 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 1 letter(s) in length. Our composite confusion score for this pair is 37944, derived from the frequency rank of both members and their visual similarity.

CPU is recorded at frequency rank #10,835, classified as anoun, pronounced /(ˌ)siː(ˌ)piːˈjuː/. crux is at rank #27,109, tagged as anoun, pronounced /kɹʌks/.

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 37944, this pair ranks #290,165 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of CPU vs crux

Shared letters: cu. Private to "CPU": p. Private to "crux": rx.

"CPU" · 3 letters · shape CCV  ·  "crux" · 4 letters · shape CCVC

Known mistypes of this pair

  • cruxccrux · crrux · cruxx · crxu · curx · rcux

Frequently Asked Questions

Is swapping "CPU" for "crux" ever safe?
No. They are said differently (/(ˌ)siː(ˌ)piːˈjuː/ versus /kɹʌks/) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Which is more common, "CPU" or "crux"?
"CPU" is the more common of the two: it sits at frequency rank #10,835 in our English list, against #27,109 for "crux". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

Eye-level mix-up between "CPU" and "crux" is sorted above. Next: full entries or other pairs that share a letter shape.

  • Full dictionary entry for "CPU" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "crux" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #290,165 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "CPU" and "crux" also get mixed up with nearby pairs, the highest-scored neighbour is "crux vs CSX". 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 #290,165 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