Sound Right

/θ/ — the TH sound (voiceless) as in think, thing, three

The main spelling (100%)

⟨th⟩ 100%

The voiceless /θ/ is always spelled ⟨th⟩.

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Voiceless means no vibration: Put your hand on your throat and say "think" — you shouldn't feel vibration during the ⟨th⟩. This is /θ/. Now say "this" — you'll feel vibration. That's the different sound /ð/.

Position patterns

Word-initial ⟨th⟩

When ⟨th⟩ starts a content word (nouns, verbs, adjectives), it's usually voiceless /θ/.

think thank third thick thief throw
Content words vs function words: Most content words starting with ⟨th⟩ use voiceless /θ/ (think, thank, three, thick). But common function words use voiced /ð/ (the, this, that, they, them, there). See the /ð/ page for those.

Word-final ⟨th⟩

At the end of nouns and adjectives, ⟨th⟩ is usually voiceless /θ/.

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/θ/ vs /ð/

Same spelling, different sounds! Both /θ/ and /ð/ are spelled ⟨th⟩. The difference is voicing: /θ/ is voiceless (think, thing, math) while /ð/ is voiced (the, this, that). Compare: breath vs breathe, bath vs bathe.

/θ/ vs /t/, /s/, /f/

Learner tip: If your language doesn't have /θ/, don't substitute /t/, /s/, or /f/! They're different sounds. Practice with: think (not "tink" or "sink"), three (not "tree" or "free"), bath (not "bat" or "bass").