USPvsUSPSWhich spelling fits?

Which to use

“USP” and “USPS” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#33,071
“USP” frequency rank
#23,149
“USPS” frequency rank
56220
confusion score

Side-by-Side Comparison

Feature USP USPS
Definition The United States Pharmacopeial Convention, Inc., a standard-setting authority that publishes USP-NF standards about pharmaceuticals and dietary supplements. Initialism of United States Postal Service.

Letter map: USP vs USPS

Shared letters muted; letters that set USP and USPS apart highlighted. Shared run: 3.

3 ch
USP
4 ch
USPS

Corpus notes: USP and USPS

USP and USPS are indexed as a confusable English pair. We have no recorded pronunciation or part of speech for both members, so the spelling overlap is what we can show you: they differ by 1 extra letter(s) - “USP” sits inside “USPS”. Our composite confusion score for this pair is 56220, derived from the frequency rank of both members and their visual similarity.

USP is recorded at frequency rank #33,071, classified as aname. USPS is at rank #23,149, tagged as aname, pronounced /ˌju ɛs pi ˈɛs/.

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 56220, this pair ranks #127,835 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of USP vs USPS

Shared letters: psu. Private to "USP": -. Private to "USPS": -.

"USP" · 3 letters · shape VCC  ·  "USPS" · 4 letters · shape VCCC

Known mistypes of this pair

  • USPSsups · upss · uspps · uspss · ussp · ussps

Frequently Asked Questions

Can "USP" and "USPS" be used interchangeably?
No. They differ by 1 extra letter(s) - “USP” sits inside “USPS”, but the dictionary glosses above give them different meanings, so swapping one for the other changes what the sentence says.
Frequency check: "USP" vs "USPS" - which ranks higher?
"USPS" is the more common of the two: it sits at frequency rank #23,149 in our English list, against #33,071 for "USP". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Done with this confusable. These links stay specific to "USP" and "USPS".

  • Full dictionary entry for "USP" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "USPS" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #127,835 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "USP" and "USPS" also get mixed up with nearby pairs, the highest-scored neighbour is "UAS vs USP". 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 #127,835 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