forthvsfourthWhat's the difference?

Quick tell: forth is a adverb, fourth is an adjective, so they fill different roles in a sentence.

Which to use

“forth” is an adverb and “fourth” is an adjective - they look or sound alike but fill different roles in a sentence.

#3,625
“forth” frequency rank
#1,562
“fourth” frequency rank
5187
confusion score

Side-by-Side Comparison

Feature forth fourth
Definition Forward in time, place or degree. The ordinal form of the number four.

Same sound, different letters: forth vs fourth

Muted letters are shared; highlighted letters are the only spelling cue when pronunciation matches. Shared run: 5 letters.

5 ch
forth
6 ch
fourth

Homophone desk: forth vs fourth

Say them out loud and nothing separates them: forth and fourth carry the same recorded pronunciation, /fɔːθ/. Grammar is what tells them apart: one is anadverb, the other anadjective, so most sentences will only accept one of them. They differ by 1 letter(s) in length. Our composite confusion score for this pair is 5187, derived from the frequency rank of both members and their visual similarity.

forth is recorded at frequency rank #3,625, classified as anadv, pronounced /fɔːθ/. fourth is at rank #1,562, tagged as anadj, pronounced /fɔːθ/.

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 5187, this pair ranks #516,276 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of forth vs fourth

Shared letters: fhort. Private to "forth": -. Private to "fourth": u.

"forth" · 5 letters · shape CVCCC  ·  "fourth" · 6 letters · shape CVVCCC

Known mistypes of this pair

  • forthfforth · forht · forrth · forthh · fortth · fotrh · ofrth
  • fourthffourth · foruth · fourht · fourrth · fourthh · fourtth · foutrh · fuorth

Frequently Asked Questions

Do "forth" and "fourth" mean the same thing in a sentence?
No - they are not even the same part of speech. "forth" is an adverb and "fourth" an adjective, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "forth" or "fourth"?
"fourth" is the more common of the two: it sits at frequency rank #1,562 in our English list, against #3,625 for "forth". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Sound matches; spelling doesn't. Use the exits below to lock the right form or check a cousin pair.

  • Full dictionary entry for "forth" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "fourth" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #516,276 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "forth" and "fourth" also get mixed up with nearby pairs, the highest-scored neighbour is "foh vs forth". 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 #516,276 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