per vs PF, What's the Difference?

Which to use

“per” is a preposition and “PF” is a noun - they look or sound alike but fill different roles in a sentence.

#339
“per” frequency rank: #16,301
“PF” frequency rank: 16640
confusion score

Side-by-Side Comparison

Feature	per	PF
Definition	For each.	Initialism of pilot flying, a pilot currently in control of the flight trajectory of the aircraft, as opposed to pilot monitoring.

Letter map: per vs PF

Shared letters muted; letters that set per and PF apart highlighted. Shared run: 1.

3 ch

per

2 ch

Spelling & Dictionary Insight

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: per is apreposition and PFanoun. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 16640, derived from the frequency rank of both members and their visual similarity.

per is recorded at frequency rank #339, classified as aprep, pronounced /pɜː/. PF is at rank #16,301, tagged as anoun.

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 16640, this pair ranks #456,493 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of per vs PF

Shared letters: p. Private to "per": er. Private to "PF": f.

"per" · 3 letters · shape CVC · "PF" · 2 letters · shape CC

Frequently Asked Questions

Can "per" and "PF" be used interchangeably?

No - they are not even the same part of speech. "per" is a preposition and "PF" a noun, so a sentence built for one is usually ungrammatical with the other.

Which is more common, "per" or "PF"?

"per" is the more common of the two: it sits at frequency rank #339 in our English list, against #16,301 for "PF". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

What to do next

You've compared "per" and "PF". Here's where to go from here.

Full dictionary entry for "per" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "PF" - compare definitions side by side with the headword page. Word entry
This pair ranks #456,493 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
"per" and "PF" also get mixed up with nearby pairs, the highest-scored neighbour is "PF vs PPA". Nearby pair

PlainSpell is a reference corpus, not spelling advice. Verify unusual forms in context.