fake vs fast, What's the Difference?

Which to use

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

#12,887
“fake” frequency rank: #8,052
“fast” frequency rank: 20939
confusion score

Side-by-Side Comparison

Feature	fake	fast
Definition	ver falso	quase

Letter map: fake vs fast

Shared letters muted; letters that set fake and fast apart highlighted. Shared run: 2.

4 ch

fake

4 ch

fast

Grammar separator: fake vs fast

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: fake is anadjective and fastanadverb. On the page they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 20939, derived from the frequency rank of both members and their visual similarity.

fake is recorded at frequency rank #12,887, classified as anadj. fast is at rank #8,052, tagged as anadv, pronounced /fast/.

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 20939, this pair ranks #49,457 of 75,631 scored Portuguese confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of fake vs fast

Shared letters: af. Private to "fake": ek. Private to "fast": st.

"fake" · 4 letters · shape CVCV · "fast" · 4 letters · shape CVCC

Known mistypes of this pair

fake ← afke · faek · fakke · ffake · fkae
fast ← afst · fasst · fastt · fats · ffast · fsat

Frequently Asked Questions

Is swapping "fake" for "fast" ever safe?

No - they are not even the same part of speech. "fake" is an adjective and "fast" an adverb, so a sentence built for one is usually ungrammatical with the other.

Frequency check: "fake" vs "fast" - which ranks higher?

"fast" is the more common of the two: it sits at frequency rank #8,052 in our Portuguese list, against #12,887 for "fake". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

Pair "fake" vs "fast" is on the table, pick a follow-up below.

Full dictionary entry for "fake" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "fast" - compare definitions side by side with the headword page. Word entry
This pair ranks #49,457 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
"fake" and "fast" also get mixed up with nearby pairs, the highest-scored neighbour is "fake vs fava". 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 #49,457 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.