KeivskuWhat's the difference?

Quick tell: Kei is a name, ku is a pronoun, so they fill different roles in a sentence.

Which to use

“Kei” is a name and “ku” is a pronoun - they look or sound alike but fill different roles in a sentence.

#29,712
“Kei” frequency rank
#29,714
“ku” frequency rank
59426
confusion score

Side-by-Side Comparison

Feature Kei ku
Definition Hipocorístico de Keila. Ese, esa. Pronombre y adjetivo demostrativo usado para una entidad ausente.

Where the eye mixes Kei and ku

Muted = shared; highlighted = the visual trap. They share 1 letter in sequence. Kei runs 3 letters (CVV) against ku's 2 (CV) - the length gap alone is often enough to separate them once you know to check it.

3 ch
Kei
2 ch
ku

Look-alike desk: Kei vs ku

These two trip readers on the page rather than in the ear: Kei is [ˈkej] while ku is [ˈku]. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 letter(s) in length, and the parts of speech differ too (name vs pronoun), which is usually the fastest check. Our composite confusion score for this pair is 59426, derived from the frequency rank of both members and their visual similarity.

Kei is recorded at frequency rank #29,712, classified as aname, pronounced [ˈkej]. ku is at rank #29,714, tagged as apron, pronounced [ˈku].

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 59426, this pair ranks #62,660 of 323,831 scored Spanish confusable pairs - among the most confusable pairs.

Orthographic DNA of Kei vs ku

Shared letters: k. Private to "Kei": ei. Private to "ku": u.

"Kei" · 3 letters · shape CVV  ·  "ku" · 2 letters · shape CV

Frequently Asked Questions

Is swapping "Kei" for "ku" ever safe?
No - they are not even the same part of speech. "Kei" is a name and "ku" a pronoun, so a sentence built for one is usually ungrammatical with the other.
Frequency check: "Kei" vs "ku" - which ranks higher?
"Kei" is the more common of the two: it sits at frequency rank #29,712 in our Spanish list, against #29,714 for "ku". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.

  • Full dictionary entry for "Kei" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "ku" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #62,660 of 323,831 scored Spanish confusable pairs in this corpus vintage. Corpus statistics
  • "Kei" and "ku" also get mixed up with nearby pairs, the highest-scored neighbour is "keen vs Kei". Nearby pair

Confusion rank #62,660 of 323,831 scored Spanish pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list