Pronunciation examples

Each table pairs pasted text with the spoken script, the words the voice receives. For the rules, see How a question becomes speech. To change a sound, see Pronunciation guides.

Formulas and reactions

Spelled letter by letter, with digits as words.

You paste	Spoken script
H2O	H two O
NaCl	N A C L
C6H12O6	C six H twelve O six
Fe3+	F E three plus
2 Na + Cl2 → 2 NaCl	2 N A plus C L two yields 2 N A C L
E = mc^2	E equals m c squared

Numbers, units, and powers of ten

Units become words. Plain numbers stay digits.

You paste	Spoken script
5 m/s	5 meters per second
890 kJ/mol	890 kilojoules per mole
25%	25 percent
6.02 × 10^23	six point oh two times ten to the twenty-third
a 2 kg cart	a 2 kilograms cart
5–10 grams	Unchanged

Fractions

Works in the stem, choices, and answer line.

You paste	Spoken script
1/7	one seventh
3/9	three ninths
2/51	two fifty-firsts
5/8	five eighths
3/2	three halves
1/360	one over three hundred sixty
50/50	fifty-fifty
2 1/2	two and one half

Text that is not a fraction

The slash in each row is not read as a fraction.

You paste	Spoken script
m/s	meters per second
and/or	Unchanged
1.5/2	Unchanged
3/9/2024	Unchanged
3 / 4	3 over 4
4/3πr3	4/3 pi r cubed

A Piper voice says a kept slash as “slash”.

Symbols and Greek letters

Symbols are said by name.

You paste	Spoken script
α-helix	alpha-helix
ΔG = ΔH − TΔS	delta G equals delta H minus T delta S
x ≤ 5	x is less than or equal to 5
√144	square root of 144
A → B	A yields B
x<3	Unchanged: a < needs spaces

Abbreviations and gene symbols

Listed initialisms and gene symbols are spelled.

You paste	Spoken script
DNA	D N A
NADPH	N A D P H
mRNA	m R N A
TP53	T P fifty-three
BRCA1	B R C A one
pH	Unchanged
NASA	Unchanged