Which to use
“their” is a determiner and “theirs” is a pronoun - they look or sound alike but fill different roles in a sentence.
- #56
- “their” frequency rank
- #7,623
- “theirs” frequency rank
- 7679
- confusion score
Side-by-Side Comparison
| Feature | their | theirs |
|---|---|---|
| Definition | Belonging to, from, of, or relating to, them (plural). | That or those belonging to them; the possessive case of they, used without a following noun. |
Where the eye mixes their and theirs
Muted = shared; highlighted = the visual trap. They share 5 letters in sequence. their runs 5 letters (CCVVC) against theirs's 6 (CCVVCC) - the length gap alone is often enough to separate them once you know to check it.
Why the eye confuses their with theirs
These two trip readers on the page rather than in the ear: their is /ðɛə/ while theirs is /ðɛəz/. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 extra letter(s) - “their” sits inside “theirs”, and the parts of speech differ too (determiner vs pronoun), which is usually the fastest check. Our composite confusion score for this pair is 7679, derived from the frequency rank of both members and their visual similarity.
their is recorded at frequency rank #56, classified as adet, pronounced /ðɛə/. theirs is at rank #7,623, tagged as apron, pronounced /ðɛəz/.
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 7679, this pair ranks #506,065 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.
Orthographic DNA of their vs theirs
Shared letters: ehirt. Private to "their": -. Private to "theirs": s.
"their" · 5 letters · shape CCVVC · "theirs" · 6 letters · shape CCVVCC
Known mistypes of this pair
Frequently Asked Questions
Is swapping "their" for "theirs" ever safe?
Frequency check: "their" vs "theirs" - which ranks higher?
Useful next steps
Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.
- Full dictionary entry for "their" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "theirs" - compare definitions side by side with the headword page. Word entry
- This pair ranks #506,065 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "their" and "theirs" also get mixed up with nearby pairs, the highest-scored neighbour is "theirs vs theism". 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 #506,065 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.