Sound Right

/z/ — the Z sound as in zoo, his, please

Main spellings (~98%)

⟨s⟩ ~60%

Surprisingly, the letter ⟨s⟩ is the most common spelling for /z/! This happens between vowels and at the end of words after voiced sounds.

his is was has please because music easy busy reason
When ⟨s⟩ sounds like /z/: The letter ⟨s⟩ often makes /z/ in these positions: (1) between vowels (music, easy, reason), (2) at the end after voiced sounds (is, his, was, has), (3) in the plural -s after voiced sounds (dogs, cars, eyes).

⟨se⟩ ~15%

Word-finally, many words use ⟨se⟩ for /z/ (the ⟨e⟩ is silent).

please because noise these those chose rise lose

⟨z⟩ ~20%

The letter ⟨z⟩ always makes /z/, but it's less common than ⟨s⟩.

zoo zero zone size freeze crazy amaze prize

⟨zz⟩ ~3%

Doubled in the middle or end of words.

buzz jazz fizz puzzle fuzzy dizzy

Unusual spellings (~2%)

⟨x⟩

At the start of words, ⟨x⟩ makes /z/.

xylophone
X at the start: When ⟨x⟩ begins a word (xylophone, xerox, xenon), it's pronounced /z/. Everywhere else, ⟨x⟩ makes /ks/ (box, fox, six).

⟨ss⟩

A handful of words spell /z/ with ⟨ss⟩.

scissors dessert possess dissolve
Scissors and dessert: Don't be fooled by the double ⟨ss⟩ — in "scissors" and "dessert," it makes /z/ not /s/. Compare: dessert (sweet, /z/) vs desert (sandy, /z/ too actually!).

/z/ vs /s/

Don't confuse /z/ with /s/! The only difference is voicing — /z/ is voiced (vocal cords vibrate) while /s/ is voiceless. The same letter ⟨s⟩ can spell either sound! Compare: zeal vs seal, prize vs price, rise vs rice.