constrainvsconstraintTell them apart

Quick tell: constrain is a verb, constraint is a noun, so they fill different roles in a sentence.

Which to use

“constrain” is a verb and “constraint” is a noun - they look or sound alike but fill different roles in a sentence.

#36,089
“constrain” frequency rank
#20,072
“constraint” frequency rank
56161
confusion score

Side-by-Side Comparison

Feature constrain constraint
Definition To force physically, by strong persuasion or pressuring; to compel; to oblige. Something that constrains; a restriction.

Where the eye mixes constrain and constraint

Muted = shared; highlighted = the visual trap. They share 9 letters in sequence.

9 ch
constrain
10 ch
constraint

Look-alike desk: constrain vs constraint

These two trip readers on the page rather than in the ear: constrain is /kənˈstɹeɪn/ while constraint is /kənˈstɹeɪnt/. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 extra letter(s) - “constrain” sits inside “constraint”, and the parts of speech differ too (verb vs noun), which is usually the fastest check. Our composite confusion score for this pair is 56161, derived from the frequency rank of both members and their visual similarity.

constrain is recorded at frequency rank #36,089, classified as averb, pronounced /kənˈstɹeɪn/. constraint is at rank #20,072, tagged as anoun, pronounced /kənˈstɹeɪnt/.

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 56161, this pair ranks #128,246 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of constrain vs constraint

Shared letters: acinorst. Private to "constrain": -. Private to "constraint": -.

"constrain" · 9 letters · shape CVCCCCVVC  ·  "constraint" · 10 letters · shape CVCCCCVVCC

Known mistypes of this pair

  • constraincconstrain · cnostrain · connstrain · consrtain · consstrain · constarin · constrainn · constrani
  • constraintcconstraint · cnostraint · connstraint · consrtaint · consstraint · constarint · constrainnt · constraintt

Frequently Asked Questions

Can "constrain" and "constraint" be used interchangeably?
No - they are not even the same part of speech. "constrain" is a verb and "constraint" a noun, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "constrain" or "constraint"?
"constraint" is the more common of the two: it sits at frequency rank #20,072 in our English list, against #36,089 for "constrain". 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 "constrain" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "constraint" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #128,246 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "constrain" and "constraint" also get mixed up with nearby pairs, the highest-scored neighbour is "constrain vs constrained". 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 #128,246 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