informvsinformalWhich spelling fits?

Quick tell: inform is a verb, informal is an adjective, so they fill different roles in a sentence.

Which to use

“inform” is a verb and “informal” is an adjective - they look or sound alike but fill different roles in a sentence.

#5,603
“inform” frequency rank
#8,682
“informal” frequency rank
14285
confusion score

Side-by-Side Comparison

Feature inform informal
Definition To instruct, train (usually in matters of knowledge). Not formal or ceremonious.

Where the eye mixes inform and informal

Muted = shared; highlighted = the visual trap. They share 6 letters in sequence. inform runs 6 letters (VCCVCC) against informal's 8 (VCCVCCVC) - the length gap alone is often enough to separate them once you know to check it.

6 ch
inform
8 ch
informal

Look-alike desk: inform vs informal

These two trip readers on the page rather than in the ear: inform is /ɪnˈfɔɹm/ while informal is /ɪnˈfɔɹm(ə)l/. Spoken aloud the problem disappears. In writing it persists, because they differ by 2 extra letter(s) - “inform” sits inside “informal”, and the parts of speech differ too (verb vs adjective), which is usually the fastest check. Our composite confusion score for this pair is 14285, derived from the frequency rank of both members and their visual similarity.

inform is recorded at frequency rank #5,603, classified as averb, pronounced /ɪnˈfɔɹm/. informal is at rank #8,682, tagged as anadj, pronounced /ɪnˈfɔɹm(ə)l/.

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 14285, this pair ranks #470,959 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of inform vs informal

Shared letters: fimnor. Private to "inform": -. Private to "informal": al.

"inform" · 6 letters · shape VCCVCC  ·  "informal" · 8 letters · shape VCCVCCVC

Known mistypes of this pair

  • inform ← ifnorm · infform · infomr · informm · inforrm · infrom · innform · inofrm
  • informal ← ifnormal · infformal · infomral · inforaml · informall · informla · informmal · inforrmal

Frequently Asked Questions

Is swapping "inform" for "informal" ever safe?
No - they are not even the same part of speech. "inform" is a verb and "informal" an adjective, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "inform" or "informal"?
"inform" is the more common of the two: it sits at frequency rank #5,603 in our English list, against #8,682 for "informal". 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 "inform" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "informal" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #470,959 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "inform" and "informal" also get mixed up with nearby pairs, the highest-scored neighbour is "infirm vs inform". 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 #470,959 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