fas vs fast, What's the Difference?

Which to use

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

#38,095
“fas” frequency rank: #243
“fast” frequency rank: 38338
confusion score

Side-by-Side Comparison

Feature	fas	fast
Definition	2. Person Singular Imperativ Präsens Aktiv des Verbs fasen	nicht ganz

Where the spellings diverge

Shared letters are muted; the letters that actually set fas and fast apart are highlighted. They share 3 letters in sequence, which is exactly why the eye skips the difference.

3 ch

fas

4 ch

fast

Spelling & Dictionary Insight

These two trip readers on the page rather than in the ear: fas is [faːs] while fast is [fast]. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 extra letter(s) - “fas” sits inside “fast”, and the parts of speech differ too (verb vs adverb), which is usually the fastest check. Our composite confusion score for this pair is 38338, derived from the frequency rank of both members and their visual similarity.

fas is recorded at frequency rank #38,095, classified as averb, pronounced [faːs]. fast is at rank #243, 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 38338, this pair ranks #1,566,570 of 2,006,359 scored German confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of fas vs fast

Shared letters: afs. Private to "fas": -. Private to "fast": t.

"fas" · 3 letters · shape CVC · "fast" · 4 letters · shape CVCC

Known mistypes of this pair

fast ← afst · fastt · fats · ffast · fsat

Frequency comparison

fas#38,095

fast#243

Source: FrequencyWords open word-frequency list

Frequently Asked Questions

Can "fas" and "fast" be used interchangeably?

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

Which is more common, "fas" or "fast"?

"fast" is the more common of the two: it sits at frequency rank #243 in our German list, against #38,095 for "fas". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

Remembering fas vs fast

The fastest way to pick the right one every time.

Check the role first: if you need a verb, it's “fas”; for an adverb, it's “fast”.
See each word in full, definition, IPA, etymology and its other confusables. Full “fas” entry
Browse more pairs most likely to be confused. Most confusable