theirvstheyWhat's the difference?

Quick tell: their is a determiner, they is a pronoun, so they fill different roles in a sentence.

Which to use

“their” is a determiner and “they” is a pronoun - they look or sound alike but fill different roles in a sentence.

#56
“their” frequency rank
#35
“they” frequency rank
91
confusion score

Side-by-Side Comparison

Feature their they
Definition Belonging to, from, of, or relating to, them (plural). A group of entities previously mentioned.

Where the eye mixes their and they

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

5 ch
their
4 ch
they

Spelling & Dictionary Insight

These two trip readers on the page rather than in the ear: their is /ðɛə/ while they is /ˈðeɪ̯/. 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 (determiner vs pronoun), which is usually the fastest check. Our composite confusion score for this pair is 91, derived from the frequency rank of both members and their visual similarity.

their is recorded at frequency rank #56, classified as adet, pronounced /ðɛə/. they is at rank #35, tagged as apron, pronounced /ˈðeɪ̯/.

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 91, this pair ranks #529,902 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of their vs they

Shared letters: eht. Private to "their": ir. Private to "they": y.

"their" · 5 letters · shape CCVVC  ·  "they" · 4 letters · shape CCVV

Known mistypes of this pair

  • theirhteir · tehir · theirr · theri · thheir · ttheir
  • theyhtey · tehy · theyy · thhey · thye · tthey

Frequently Asked Questions

Can "their" and "they" be used interchangeably?
No - they are not even the same part of speech. "their" is a determiner and "they" a pronoun, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "their" or "they"?
"they" is the more common of the two: it sits at frequency rank #35 in our English list, against #56 for "their". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

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

Source: FrequencyWords open word-frequency list