skimvssumWhich spelling fits?

Quick tell: skim is a verb, sum is a noun, so they fill different roles in a sentence.

Which to use

“skim” is a verb and “sum” is a noun - they look or sound alike but fill different roles in a sentence.

#23,397
“skim” frequency rank
#4,050
“sum” frequency rank
27447
confusion score

Side-by-Side Comparison

Feature skim sum
Definition To pass lightly; to glide along in an even, smooth course; to glide along near the surface. A quantity obtained by addition or aggregation.

Where the eye mixes skim and sum

Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.

4 ch
skim
3 ch
sum

Look-alike desk: skim vs sum

These two trip readers on the page rather than in the ear: skim is /skɪm/ while sum is /sʌm/. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 letter(s) in length, and the parts of speech differ too (verb vs noun), which is usually the fastest check. Our composite confusion score for this pair is 27447, derived from the frequency rank of both members and their visual similarity.

skim is recorded at frequency rank #23,397, classified as averb, pronounced /skɪm/. sum is at rank #4,050, tagged as anoun, pronounced /sʌm/.

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 27447, this pair ranks #378,825 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of skim vs sum

Shared letters: ms. Private to "skim": ik. Private to "sum": u.

"skim" · 4 letters · shape CCVC  ·  "sum" · 3 letters · shape CVC

Known mistypes of this pair

  • skimksim · sikm · skimm · skkim · skmi · sskim

Frequently Asked Questions

Is swapping "skim" for "sum" ever safe?
No - they are not even the same part of speech. "skim" is a verb and "sum" a noun, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "skim" or "sum"?
"sum" is the more common of the two: it sits at frequency rank #4,050 in our English list, against #23,397 for "skim". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.

  • Full dictionary entry for "skim" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "sum" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #378,825 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "skim" and "sum" also get mixed up with nearby pairs, the highest-scored neighbour is "Sif vs skim". 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 #378,825 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