Which to use
“firth” and “froth” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.
- #22,972
- “firth” frequency rank
- #39,329
- “froth” frequency rank
- 62301
- confusion score
Side-by-Side Comparison
| Feature | firth | froth |
|---|---|---|
| Definition | An arm or inlet of the sea; a river estuary. | Foam. |
Where the eye mixes firth and froth
Muted = shared; highlighted = the visual trap. They share 4 letters in sequence. firth (CVCCC) and froth (CCVCC) run the same length but a different consonant-vowel pattern - the shape difference is usually the fastest tell.
Why the eye confuses firth with froth
A purely visual mix-up. firth (/fɜːθ/) and froth (/fɹɒθ/) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 62301, derived from the frequency rank of both members and their visual similarity.
firth is recorded at frequency rank #22,972, classified as anoun, pronounced /fɜːθ/. froth is at rank #39,329, tagged as anoun, pronounced /fɹɒθ/.
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 62301, this pair ranks #89,288 of 530,003 scored English confusable pairs - among the most confusable pairs.
Orthographic DNA of firth vs froth
Shared letters: fhrt. Private to "firth": i. Private to "froth": o.
"firth" · 5 letters · shape CVCCC · "froth" · 5 letters · shape CCVCC
Known mistypes of this pair
Frequently Asked Questions
Is swapping "firth" for "froth" ever safe?
Frequency check: "firth" vs "froth" - which ranks higher?
What to do next
Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.
- Full dictionary entry for "firth" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "froth" - compare definitions side by side with the headword page. Word entry
- This pair ranks #89,288 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "firth" and "froth" also get mixed up with nearby pairs, the highest-scored neighbour is "foh vs froth". 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 #89,288 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.