nullvsnuloTell them apart

Quick tell: null is a num, nulo is an adjective, so they fill different roles in a sentence.

Which to use

“null” is a num and “nulo” is an adjective - they look or sound alike but fill different roles in a sentence.

#42,573
“null” frequency rank
#18,400
“nulo” frequency rank
60973
confusion score

Side-by-Side Comparison

Feature null nulo
Definition o número zero que não existe

Where the eye mixes null and nulo

Muted = shared; highlighted = the visual trap. They share 3 letters in sequence.

4 ch
null
4 ch
nulo

Visual trap between null and nulo

These two trip readers on the page rather than in the ear: null is /nʊl/ ouvir^(fonte ?) while nulo is /ˈnu.lu/. Spoken aloud the problem disappears. In writing it persists, because they differ by a single letter - l in “null” becomes o in “nulo”, and the parts of speech differ too (num vs adjective), which is usually the fastest check. Our composite confusion score for this pair is 60973, derived from the frequency rank of both members and their visual similarity.

null is recorded at frequency rank #42,573, classified as anum, pronounced /nʊl/ ouvir^(fonte ?). nulo is at rank #18,400, tagged as anadj, pronounced /ˈnu.lu/.

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 60973, this pair ranks #7,380 of 75,631 scored Portuguese confusable pairs - among the most confusable pairs.

Orthographic DNA of null vs nulo

Shared letters: lnu. Private to "null": -. Private to "nulo": o.

"null" · 4 letters · shape CVCC  ·  "nulo" · 4 letters · shape CVCV

Known mistypes of this pair

  • nullnlul · nnull · nul · unll
  • nulonluo · nnulo · nullo · nuol · unlo

Frequently Asked Questions

Can "null" and "nulo" be used interchangeably?
No - they are not even the same part of speech. "null" is a num and "nulo" an adjective, so a sentence built for one is usually ungrammatical with the other.
In ordinary Portuguese text, does "null" or "nulo" show up more?
"nulo" is the more common of the two: it sits at frequency rank #18,400 in our Portuguese list, against #42,573 for "null". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.

  • Full dictionary entry for "null" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "nulo" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #7,380 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
  • "null" and "nulo" also get mixed up with nearby pairs, the highest-scored neighbour is "null vs nun". 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 #7,380 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