impurevsinsureWhich spelling fits?

Quick tell: impure is a adjective, insure is a verb, so they fill different roles in a sentence.

Which to use

“impure” is an adjective and “insure” is a verb - they look or sound alike but fill different roles in a sentence.

#30,840
“impure” frequency rank
#17,164
“insure” frequency rank
48004
confusion score

Side-by-Side Comparison

Feature impure insure
Definition Not pure To provide for compensation if some specified risk occurs. Often agreed by policy (contract) to offer financial compensation in case of an accident, theft or other undesirable event.

Where the eye mixes impure and insure

Muted = shared; highlighted = the visual trap. They share 4 letters in sequence. impure and insure follow the identical consonant-vowel pattern (VCCVCV). Same shape at a glance is often the real trap, independent of shared letters.

6 ch
impure
6 ch
insure

Visual trap between impure and insure

These two trip readers on the page rather than in the ear: impure is /ɪmˈpjʊə(ɹ)/ while insure is /ɪnˈʃɔː(ɹ)/. Spoken aloud the problem disappears. In writing it persists, because they share most of their letters but differ in 2 positions, and the parts of speech differ too (adjective vs verb), which is usually the fastest check. Our composite confusion score for this pair is 48004, derived from the frequency rank of both members and their visual similarity.

impure is recorded at frequency rank #30,840, classified as anadj, pronounced /ɪmˈpjʊə(ɹ)/. insure is at rank #17,164, tagged as averb, pronounced /ɪnˈʃɔː(ɹ)/.

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 48004, this pair ranks #197,233 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of impure vs insure

Shared letters: eiru. Private to "impure": mp. Private to "insure": ns.

"impure" · 6 letters · shape VCCVCV  ·  "insure" · 6 letters · shape VCCVCV

Known mistypes of this pair

  • impure ← immpure · imppure · imprue · impuer · impurre · imupre · ipmure · mipure
  • insure ← innsure · insrue · inssure · insuer · inusre · isnure · nisure

Frequently Asked Questions

Do "impure" and "insure" mean the same thing in a sentence?
No - they are not even the same part of speech. "impure" is an adjective and "insure" a verb, so a sentence built for one is usually ungrammatical with the other.
In ordinary English text, does "impure" or "insure" show up more?
"insure" is the more common of the two: it sits at frequency rank #17,164 in our English list, against #30,840 for "impure". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

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

  • Full dictionary entry for "impure" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "insure" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #197,233 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "impure" and "insure" also get mixed up with nearby pairs, the highest-scored neighbour is "implore vs impure". 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 #197,233 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