How to Pronounce the TH Sound in English

1. She thought carefully before giving her answer to the difficult question on the exam.
2. They drove through the thick fog on their way to the northern coast.
3. He thanked his mother for everything she had done throughout his entire childhood.
4. Think carefully and breathe slowly before you answer the three questions at the end.
5. The weather was cold and the path through the forest was barely visible in the early morning light.

The TH sound is one of the most challenging features of English pronunciation for speakers from almost any other language. English uses two completely distinct TH sounds: the voiceless /θ/ as in “think,” “three,” and “bath,” and the voiced /ð/ as in “the,” “this,” and “breathe.” Both require placing your tongue at or between your front teeth - a physical position that simply does not exist in the sound systems of Tagalog, Hindi, Mandarin, Japanese, or most European languages. The result is that even advanced learners frequently replace TH with /t/, /d/, /s/, or /z/ without realizing it. This guide covers both sounds completely: tongue position, mouth mechanics, the exact reason most learners get them wrong, and a structured drill sequence that takes you from zero to confident.

IPA Pronunciation of the TH Sound

English has two phonemes written with the letters “th.” They share the same tongue position but differ in one key variable - vocal cord vibration.

Voiceless TH: /θ/ (no vocal cord vibration)

American English: /θ/ · British English: /θ/

Common words: think /θɪŋk/, three /θriː/, bath /bæθ/, thumb /θʌm/, thanks /θæŋks/, thorough /ˈθɜːrəʊ/, author /ˈɔːθər/, athlete /ˈæθ.liːt/

Voiced TH: /ð/ (with vocal cord vibration)

American English: /ð/ · British English: /ð/

Common words: the /ðə/, this /ðɪs/, that /ðæt/, they /ðeɪ/, breathe /briːð/, mother /ˈmʌð.ər/, weather /ˈweð.ər/, feather /ˈfeð.ər/

The quickest test to tell them apart: press your fingertips gently against your throat. Say “the” (/ð/) - you should feel a clear buzz or vibration. Say “think” (/θ/) - no buzz, just a stream of air. That physical difference is the entire distinction between the two TH sounds. In IPA notation, the /θ/ symbol comes from the Greek letter theta, and /ð/ is named “eth” - the Old English runic letter that originally represented the voiced TH sound.

Step-by-Step Guide to Producing the TH Sound

Both TH sounds require the same tongue position. The only difference is whether your vocal cords are active.

1. Step 1: Set the tongue position (for both /θ/ and /ð/)
2. Place the tip of your tongue so it gently touches the back edge of your upper front teeth - or push it slightly further forward so the tongue tip peeks between your upper and lower teeth. Your tongue should be flat and completely relaxed - not curled, not tense. Your upper teeth should rest lightly on the top of your tongue tip, and your jaw should be slightly open. This is the interdental position. If you cannot feel your teeth touching your tongue tip, you are in the wrong place - move your tongue forward until you can.
3. Step 2: Voiceless TH /θ/ - for “think,” “three,” “bath”
4. With your tongue in position, push a steady, continuous stream of air between your tongue and upper teeth. Do not close the gap - let the air flow freely through. Your vocal cords should be completely still: no buzzing, no humming, just clean airflow. Hold your hand in front of your mouth. For /θ/ in “think,” you should feel a cool, steady stream of air on your palm. The sensation is similar to /f/ or /s/ but produced further forward, with your tongue against the teeth rather than behind them.
5. Step 3: Voiced TH /ð/ - for “the,” “this,” “breathe”
6. Same tongue position. Same continuous airflow. The only addition: activate your vocal cords. Hum gently as you push the air through. You will feel a vibration at the very tip of your tongue where it meets your teeth, and a clear buzz in your throat. Press two fingers against your throat just below the jaw. For /ð/ in “the,” the vibration is immediate and unmistakable - like a gentle electric pulse. If you feel nothing, your vocal cords are not engaging.

Combine them: alternate between “think” (/θ/) and “the” (/ð/), switching the vocal cord vibration on and off while keeping your tongue in exactly the same position. Once you can do this smoothly, both sounds are locked in.

Why Does English Have TH Sounds?

This is where most guides stop - but understanding the origin makes these sounds easier to accept and remember permanently.

The TH sounds (/θ/ and /ð/) are among the oldest sounds in English, descending directly from Proto-Germanic and inherited through Old English (spoken roughly 450 to 1150 AD). Old English scribes used two dedicated runic letters for these sounds: “thorn” (þ) for the voiceless /θ/ and “eth” (ð) for the voiced /ð/. These were not rare or borrowed sounds - they were core to the language. “Þe” meant “the,” “þink” became “think,” “ðis” became “this,” and “ðey” became “they.” English-speaking communities used these sounds every single day, in the most common words in the language.

The shift began with the Norman Conquest of 1066. Norman French speakers brought the Latin alphabet to England, and Latin had no letters for /θ/ or /ð/ - Latin had lost these sounds centuries earlier, likely by the 1st century AD. As Norman scribes standardized English writing over the 12th and 13th centuries, the runic þ and ð gradually disappeared from manuscripts. The solution they landed on was the digraph “th” - using two existing Latin letters to represent a sound that Latin itself never had. By the 14th century, “th” had completely replaced both runic characters in written English. The pronunciation never changed; only the written symbol did.

Today, /θ/ and /ð/ are among the rarest phonemes in the world's languages. The World Atlas of Language Structures estimates that fewer than 10 percent of the world's approximately 7,000 languages use either sound. The languages that do include them form a very short list: English, Modern Greek, Arabic (ث for /θ/ and ذ for /ð/), Icelandic, Welsh, Basque, and a handful of others. Spanish, French, Portuguese, Italian, German, Mandarin, Japanese, Hindi, Tagalog - none of them have /θ/ or /ð/ as native phonemes. This is why the TH sound feels genuinely hard for most learners: it is not a matter of not trying hard enough - the brain has simply never practiced this precise tongue position in the context of producing speech.

Voiceless TH /θ/ vs Voiced TH /ð/

The Voiceless TH /θ/

The voiceless /θ/ appears most often at the start of content words - nouns, verbs, adjectives, and adverbs that carry meaning: think, three, thumb, thanks, thorough, thousand, thick, thin, theme, threat, throat, through, throw. It also appears at the end of many nouns: bath, cloth, moth, math, mouth, tooth, birth, death, breath. And it appears in the middle of words: author, athlete, anthem, cathedral, method, pathetic, arithmetic. A useful rule: if the word is a content word (something with independent meaning) that begins or ends with “th,” it almost always uses /θ/.

The Voiced TH /ð/

The voiced /ð/ dominates function words - the grammatical glue that holds sentences together: the, this, that, these, those, they, them, their, there, then, than, though, although, whether. These are the words you use hundreds of times per day. The /ð/ also appears in the middle and end of common words: mother, father, brother, other, either, together, weather, feather, breathe, soothe, bathe, loathe. The pattern to remember: short function words almost always use /ð/; longer content words almost always use /θ/. “The” (most common English word) is /ð/. “Think” (content word) is /θ/. This rule holds in about 90 percent of cases.

Minimal Pairs - Train Your Ear

Minimal pairs are words that differ by only one sound. These three pairs isolate the key contrasts in the TH sounds.

1. think /θɪŋk/ vs tick /tɪk/ - The only difference is /θ/ vs /t/ at the start. In “tick,” the tongue touches the ridge just behind the upper teeth and releases with a small burst of air (/t/). In “think,” the tongue presses against or between the teeth and lets air flow continuously (/θ/). Drilling this pair isolates the exact movement that most Filipino and Indian learners need to retrain. Say “tick” first, notice where your tongue is, then move it forward to the teeth for “think.”
2. three /θriː/ vs tree /triː/ - Near-identical: the only difference is the initial /θ/ vs /t/ before the /r/. Many learners say “tree” for “three” and never notice the error because the words sound very similar at speed. The /θr/ cluster in “three” requires placing the tongue at the teeth before connecting to the /r/ - not touching the alveolar ridge as in /tr/. Practice slowly: “ththth-ree” before linking the sounds.
3. then /ðɛn/ vs den /dɛn/ - The only difference is /ð/ vs /d/ at the start. “Den” uses the tongue tip pressed firmly against the alveolar ridge (the bumpy area behind the upper teeth), then released: /d/. “Then” uses the tongue pressed gently against the back of the teeth or between the teeth, with continuous airflow and vocal cord buzz: /ð/. The physical distance between these two positions is only a few millimeters forward - but the acoustic result is completely different. Alternate 10 times: den, then, den, then.

Say each pair out loud five times. If the sounds blur together, slow down and hold the TH sound for two full seconds before completing the word.

Common Mistakes When Pronouncing TH

These are the specific errors non-native speakers make most often - each with its exact root cause:

1. Mistake 1 - Replacing /θ/ with /t/ and /ð/ with /d/ (especially Filipino speakers): “Think” becomes “tink,” “three” becomes “tree,” “then” becomes “den,” and “the” sounds like “de.” This is by far the most widespread TH substitution globally. Tagalog and other Philippine languages have /t/ and /d/ as their closest available sounds, and both are dental in Filipino English (produced with the tongue touching the back of the upper teeth) - which is physically close to the TH position. The critical difference is what happens after the tongue contacts the teeth: for /t/ and /d/, the tongue presses and releases, producing a burst of air. For /θ/ and /ð/, the tongue stays in contact and air flows continuously through the gap. The fix: say “t” and hold the position - then gradually push your tongue forward until it touches the teeth and let air flow without releasing. That continuous airflow is /θ/.
2. Mistake 2 - Replacing /θ/ with /s/ and /ð/ with /z/ (especially Indian speakers): “Think” becomes “sink,” “three” becomes “sree,” “this” becomes “zis,” and “the” sounds like “ze.” Hindi has no interdental fricatives, and /s/ and /z/ are the closest continuous consonants in the Hindi sound system - both are fricatives like /θ/ and /ð/, just produced further back in the mouth. Speakers whose L1 is Hindi, Bengali, Gujarati, or Telugu often default to this substitution because the airflow quality of /s/ feels similar to /θ/. The fix is the same tongue position check: for /s/ and /z/, your tongue is behind your teeth, aimed at the alveolar ridge. For /θ/ and /ð/, the tongue must move forward until it touches the teeth. Feel the teeth on your tongue - if you cannot, you are producing /s/ or /z/.
3. Mistake 3 - Confusing voiced and voiceless TH: Learners who have mastered the tongue position sometimes still use /θ/ where /ð/ belongs and vice versa. The most common version is using /θ/ (voiceless) for all TH words, including function words like “the” and “this” that should use /ð/ (voiced). This produces an unnaturally breathy quality in common speech - every “the” sounds like an airy breath. The root cause is that /θ/ is easier to produce (no vocal cord coordination needed) and learners default to it. The fix is the buzz test: every time you say a short function word (the, this, that, they, them, then, those), consciously switch on your vocal cords. Press your fingers to your throat and confirm the buzz is there. Commit to making every “the” buzz.

Practice Tips

1. The Mirror Test: Practice in front of a mirror and check that your tongue tip is visible between or touching your teeth. If you cannot see your tongue at all when producing TH, you are making /t/, /d/, /s/, or /z/ instead. Visibility of the tongue tip is not strictly required (some speakers keep the tongue just at the teeth without protruding), but if you are still learning the sound, seeing the tongue confirms you are in the right place.
2. The Buzz Test: Place two fingers against your throat every time you practice. “The,” “this,” “they,” “breathe” - you must feel a buzz. “Think,” “three,” “bath,” “thanks” - no buzz, only airflow. Running this check in real time builds the habit faster than any amount of isolated drilling.
3. Record and Compare: Use the Pronounce Checker tool above to score your pronunciation with real audio feedback. Try the sentence “The three thin brothers thought thoroughly” - it alternates between /ð/ and /θ/ and covers both sounds in a single phrase.
4. The Single-Word Habit: “The” is the most common word in English and contains /ð/. Commit to producing it correctly every single time you speak. Since you say “the” hundreds of times per day, this single-word habit gives you more /ð/ practice than any structured exercise can provide. Every sentence is a drill.
5. Related Words: The /θ/ sound appears prominently in our guide to how to pronounce thorough - a word that uses /θ/ at the start and is itself commonly mispronounced. For a broader view of English pronunciation traps, see our roundup of the 10 most commonly mispronounced English words.

Frequently Asked Questions

How do you pronounce TH in American English?

In American English, TH represents two sounds: the voiceless /θ/ (think, bath) and the voiced /ð/ (the, this). Both are identical in IPA between American and British English - the tongue position and the presence or absence of vocal cord vibration are the same in both accents. The TH sounds themselves are not one of the areas where American and British pronunciation diverge.

Is the TH in “the” different from the TH in “think”?

Yes - they are two completely different phonemes. “The” uses the voiced /ð/: your vocal cords are active and you can feel a buzz in your throat. “Think” uses the voiceless /θ/: no vocal cord vibration, only a steady stream of air. The tongue position is identical for both - tip at or between the upper front teeth. The buzz test is the fastest way to feel the difference: press your fingers to your throat, say “the,” and confirm the vibration before saying “think” and confirming its absence.

What words use the voiceless TH /θ/?

Common voiceless /θ/ words include: think, three, thumb, thanks, thick, thin, thorough, thousand, theme, throat, through, bath, cloth, moth, math, mouth, tooth, birth, death, breath, author, athlete, and cathedral. The clearest pattern: if the TH word is a content word (a noun, verb, adjective, or adverb) starting or ending with “th,” it almost always uses /θ/. Function words (the, this, that, they) almost always use /ð/ instead.

How many TH sounds does English have?

Standard English has exactly two TH sounds: /θ/ (voiceless, as in think) and /ð/ (voiced, as in the). There is no third TH phoneme in native English words. In some borrowed words, “th” can be pronounced as /t/ (as in Thomas, Theresa, or Thames) or as separate /t/ + /h/ sounds, but these are foreign-origin exceptions - the core English TH phoneme is always either /θ/ or /ð/.

Quick Recap

1. Two TH sounds: voiceless /θ/ (think, bath, three) and voiced /ð/ (the, this, breathe). Same tongue position - the only difference is vocal cord vibration.
2. Tongue position for both: tip of tongue at or between the upper front teeth, flat and relaxed, with air flowing continuously through the gap.
3. The /ð/ dominates function words (the, this, that, they, them). The /θ/ dominates content words (think, three, bath, thanks, thorough). This rule covers about 90 percent of cases.
4. Use the buzz test: press fingers to your throat. “The” buzzes. “Think” does not. Build both sounds by making every “the” you speak into a /ð/ drill.

Use the practice tool above to check your TH pronunciation with real audio feedback. Happy practicing!