sivsWhat's the difference?

Quick tell: si is a pronoun, is an adjective, so they fill different roles in a sentence.

Which to use

“si” is a pronoun and “só” is an adjective - they look or sound alike but fill different roles in a sentence.

#482
“si” frequency rank
#50
“só” frequency rank
532
confusion score

Side-by-Side Comparison

Feature si
Definition refere-se à terceira pessoa, indica reflexividade e é usado após preposição (a, de, em, contra, sobre, por, etc., exceto com) solitário, sem companhia, sem círculo social

Where the eye mixes si and só

Muted = shared; highlighted = the visual trap. They share 1 letter in sequence.

2 ch
si
2 ch
só

Visual trap between si and só

These two trip readers on the page rather than in the ear: si is /ˈsi/ while is /ˈsɔ/. Spoken aloud the problem disappears. In writing it persists, because they differ by a single letter - i in “si” becomes ó in “só”, and the parts of speech differ too (pronoun vs adjective), which is usually the fastest check. Our composite confusion score for this pair is 532, derived from the frequency rank of both members and their visual similarity.

si is recorded at frequency rank #482, classified as apron, pronounced /ˈsi/. is at rank #50, tagged as anadj, pronounced /ˈsɔ/.

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 532, this pair ranks #75,137 of 75,631 scored Portuguese confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of si vs só

Shared letters: s. Private to "si": i. Private to "só": ó.

"si" · 2 letters · shape CV  ·  "só" · 2 letters · shape CV

Frequently Asked Questions

Can "si" and "só" be used interchangeably?
No - they are not even the same part of speech. "si" is a pronoun and "só" an adjective, so a sentence built for one is usually ungrammatical with the other.
In ordinary Portuguese text, does "si" or "só" show up more?
"só" is the more common of the two: it sits at frequency rank #50 in our Portuguese list, against #482 for "si". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Eye-level mix-up between "si" and "só" is sorted above. Next: full entries or other pairs that share a letter shape.

  • Full dictionary entry for "si" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "só" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #75,137 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
  • "si" and "só" also get mixed up with nearby pairs, the highest-scored neighbour is "só vs soap". Nearby pair

Confusion rank #75,137 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list