paivspHWhich spelling fits?

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

Which to use

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

#34,232
“pai” frequency rank
#10,377
“pH” frequency rank
44609
confusion score

Side-by-Side Comparison

Feature pai pH
Definition Deuxième personne du singulier de l’indicatif présent de pular. Opposé du logarithme décimal de la concentration en ions hydroniums d’une solution aqueuse. Échelle de mesure de l’acidité d’une solution. ( pH = -log₁₀ [H⁺])

Where the eye mixes pai and pH

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

3 ch
pai
2 ch
pH

Look-alike desk: pai vs pH

These two trip readers on the page rather than in the ear: pai is [ˈpa.i] while pH is \pe.aʃ\. 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 44609, derived from the frequency rank of both members and their visual similarity.

pai is recorded at frequency rank #34,232, classified as averb, pronounced [ˈpa.i]. pH is at rank #10,377, tagged as anoun, pronounced \pe.aʃ\.

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 44609, this pair ranks #209,172 of 440,172 scored French confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of pai vs pH

Shared letters: p. Private to "pai": ai. Private to "pH": h.

"pai" · 3 letters · shape CVV  ·  "pH" · 2 letters · shape CC

Frequently Asked Questions

Is swapping "pai" for "pH" ever safe?
No - they are not even the same part of speech. "pai" is a verb and "pH" a noun, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "pai" or "pH"?
"pH" is the more common of the two: it sits at frequency rank #10,377 in our French list, against #34,232 for "pai". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

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

  • Full dictionary entry for "pai" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "pH" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #209,172 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
  • "pai" and "pH" also get mixed up with nearby pairs, the highest-scored neighbour is "pai vs pio". Nearby pair

Confusion rank #209,172 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list