TTS Verbalization Guide & Specifications for en-AU

Product: en-AU
Release Date: October 2026
TTS Engine version: 3.4.0

Introduction

This document describes how specific series of strings are read by the TTS Engine for the EN language in the AU domain. The readings are the engine's current output for the version above: when a reading is not what is wanted, this document still shows what the engine does.

Convention: every example table includes an Odi voice output column. Any new row appears marked with 🆕. Missing support is shown as "unsupported". Numeric ranges use [a-b] (for example, [1-99] means any number from 1 to 99).

Readings are shown in lower case with punctuation as the engine returns it.

Numbers

Integers

Format	Example input	Odi
`[1-9][0-9]`	`25`	twenty five
`[1-9][0-9]…[0-9]`	`159`	one hundred and fifty nine
`<dash>[1-9]…[0-9]`	`-58`	minus fifty eight
`[1-9][0-9]…[0-9][0-9] (>999)`	`2824`	two thousand eight hundred and twenty four
`20[0-9][0-9]`	`2012`	twenty twelve
`[1-9][0-9]{0,2}<comma>[0-9]{3}`	`2,824`	two thousand eight hundred and twenty four

Allowed thousands delimiter: comma only. A space delimiter reads as two separate number groups ("2 824" is "two eight hundred and twenty four"). Max supported value: 999,999,999,999 (999 billion and below), read as "nine hundred and ninety nine billion nine hundred and ninety nine million nine hundred and ninety nine thousand nine hundred and ninety nine". Beyond that, digits are spelled one by one. Integers are read with "and" after hundreds and thousands. A four-digit number close to the current year is read as a year.

Ordinal numbers

Format	Example input	Odi
`[1-9]…[0-9]{st,nd,rd,th}`	`1st`	first

Decimals

Decimal separator: dot. Digits after the dot are spelled individually.

Format	Example input	Odi
`[1-9]…[0-9]<dot>[0-9]…[0-9]`	`2.4527`	two point four five two seven
`<dash>[1-9]…[0-9]<dot>[0-9]…[0-9]`	`-25.78`	minus twenty five point seven eight

Fractions and units

Format	Example input	Odi
`[1-99]<slash>[1-99]`	`13/16`	thirteen sixteenths
`[1-99]<slash>[1-99]`	`45/2`	forty five halves

A fraction that complies with the date format, thus [1-31]<slash>[1-12], is read as a date of the year if no supported unit is provided. E.g. "5/12" is read as "the fifth of december" while "5/12 km" is read as "five twelfths kilometre". A date-like fraction without a unit (for example 1/2 or 3/4) is therefore read as a date, day first.

Format	Example input	Odi
`[1-31]<slash>[1-12] <unit>`	`5/12 km`	five twelfths kilometer
`[1-31]<slash>[1-12]`	`1/2`	the first of february
`[1-31]<slash>[1-12]`	`3/4`	the third of april
`{vulgar fraction} <unit>`	`½ cup`	½ cup
`[1-99]/[1-99] <unit>`	`3/4 mile`	the third of april mile

A vulgar fraction such as ½ is not converted: the text passes through unchanged.

Digit-by-digit spelling

The dash notation can be used to spell the digit sequence digit by digit.

For Odi, the dashes are used to spell the digit sequence digit by digit, without commas between the digits.

Example input	Odi
`4-2-1-4 2-3-4 7-5-3`	four two one four two three four seven five three

Note: this notation can be used for digit sequences with more than 2 digits. Otherwise it will be verbalized as an interval. E.g. "2-3" is "two to three".

For Lexis, [pause] is a 0.025 s pause. Digits are read in groups of three, counted across the whole sequence. A comma stays where the input has a space.

16-digit card numbers

Dash notation can be used to spell out the card numbers:

Example input	Odi
`5-8-9-6 4-2-6-5 1-2-3-4 7-4-6-8`	five eight nine six four two six five one two three four seven four six eight
`5-8-9-6-4-2-6-5 1-2-3-4-7-4-6-8`	five eight nine six four two six five one two three four seven four six eight

Counter examples

The numbers in between the dashes are read as integers and the dash is pronounced as "dash" if the dash is used more than once. Unlike plain integers, these numbers are read with a comma after "thousand".
If only one dash is used, then the digit sequence is handled as an interval.
If no dash is used, the numbers are read as integers.

Example input	Odi
`4532-1234-5678-9012`	four thousand, five hundred and thirty two dash one thousand, two hundred and thirty four dash five thousand, six hundred and seventy eight dash nine thousand and twelve
`4532 1234 5678 9012`	four thousand five hundred and thirty two one thousand two hundred and thirty four five thousand six hundred and seventy eight nine thousand and twelve
`4532-1234-5678`	four thousand, five hundred and thirty two dash one thousand, two hundred and thirty four dash five thousand, six hundred and seventy eight
`4532-1234`	four thousand five hundred and thirty two to one thousand two hundred and thirty four

Telephone numbers

Format	Example input	Odi
`([0-9]{2}) [0-9]{4} [0-9]{4}`	`(02) 9876 5432`	( two ) nine thousand eight hundred and seventy six five thousand four hundred and thirty two
`04[0-9]{2} [0-9]{3} [0-9]{3}`	`0412 345 678`	four hundred and twelve three hundred and forty five six hundred and seventy eight
`+[0-9]{2} [0-9] [0-9]{4} [0-9]{4}`	`+61 2 9876 5432`	+61 two nine thousand eight hundred and seventy six five thousand four hundred and thirty two

Combination of numbers and words

Format	Example input	Odi
`[0-9]…[0-9]<dash>{word}`	`16-digit`	sixteen digit
`{word}<dash>[0-9]…[0-9]`	`COVID-19`	covid nineteen

A space around a dash between a number and a word verbalizes the dash as the word "dash" (e.g. "16 - digit" becomes "sixteen dash digit"). A spaced dash between two words is read as a pause (see Dashed words).

Ratio and intervals

Format	Example input	Odi
`[0-9]…[0-9]<colon>[0-9]…[0-9]`	`16:9`	sixteen to nine
`[0-9]…[0-9]<dash>[0-9]…[0-9]`	`16-9`	sixteen to nine
`[0-9]…[0-9]<dash>[0-9]…[0-9] {word}`	`3-5 days`	three to five days

If the ratio values overlap with the time format, the time will be announced. E.g. "24:00" is verbalized as "twenty four hours" while "25:00" is "twenty five to zero".

Percentage

Example input	Odi
`15%`	fifteen percent

Time

Format	Example input	Odi
`[00-24]<colon>[00-59]<colon>[00-59]`	`12:11:01`	twelve hours eleven minutes and one second
`[00-24]<colon>[00-59]`	`23:15`	twenty three fifteen
`[00-24]<colon>00`	`24:00`	twenty four hours
`[1-12] {PM,AM}`	`2 PM`	two p m
`[01-12]<colon>[00-59] {PM,AM}`	`02:20 PM`	two twenty p m
`00<colon>00`	`00:00`	midnight

Date

Format	Example input	Odi
`[1-31] {month} [0-9]{4}`	`14 May 2022`	the fourteenth of may, twenty twenty two
`{month} [1-31], [0-9]{4}`	`June 6, 2020`	the sixth of june, twenty twenty
`[00-31]/[00-12]/[0-9][0-9]`	`31/12/19`	the thirty first of december, nineteen
`[00-31].[00-12].[0-9]{4}`	`27.05.2021`	the twenty seventh of may, twenty twenty one
`[0-9]{4}-[00-12]-[00-31]`	`2022-11-02`	the second of november, twenty twenty two
`{month} [1-31]{st,nd,rd,th}`	`October 21st`	october twenty first
`[1-31]{st,nd,rd,th} {month}`	`21st October`	twenty first october
`[1-31]/[1-12]`	`23/5`	the twenty third of may
`[1-31]/[1-12]`	`5/12`	the fifth of december

Note: Dates are day first (en-US reads month first) and are read with "the" before the day and "of" before the month. A two-digit year is read as a number ("nineteen").

Units

Format	Example input	Odi
`{amount}{unit}`	`2.5GB`	2. 5gb
`{amount}<space>{unit}`	`1.5 GB`	one point five g b
`{amount}<space>{unit}`	`3 m`	three meters
`{amount}{unit}/{unit}`	`1500MB/s`	1500mb slash s
`{amount}<space>{unit}/{unit}`	`1400 MB/s`	one thousand four hundred m b slash s

Supported unit abbreviations

This table is the voice-package unit table. Without it the engine reads only a few units, such as km and l. Units such as mm, ft and mph are not read.

Abbreviation	Odi
`mm`	mm
`cm`	centimeter / centimeters
`m`	meter / meters
`km`	kilometer / kilometers
`Km`	kilometer / kilometers
`m²`	square meter / square meters
`m2`	square meter / square meters
`m³`	m³
`m3`	m3
`"`	inch / inches
`in`	in
`'`	foot / feet
`ft`	ft
`yd`	yd
`mi`	mi
`mph`	mph
`MPH`	m p h
`h`	hour / hours
`hr`	hr
`min`	min
`mins`	mins
`s`	second / seconds
`g`	g
`gm`	gm
`kg`	kg
`Kg`	kg
`oz`	oz
`lb`	lb
`lbs`	lbs
`ml`	ml
`mL`	ml
`l`	liter / liters
`L`	l
`gal`	gal
`cup`	cup
`Hz`	hz
`hz`	hz
`kHz`	khz
`MHz`	mhz
`GHz`	ghz
`W`	w
`kW`	kw
`MW`	m w
`GW`	g w
`V`	v
`mA`	ma
`A`	a
`dB`	db
`kb`	kb
`mb`	mb
`gb`	gb
`tb`	tb
`pb`	pb
`kB`	kb
`MB`	m b
`GB`	g b
`TB`	t b
`PB`	p b
`bps`	bps
`Kbps`	kbps
`Mbps`	mbps
`Gbps`	gbps
`Tbps`	tbps
`kBps`	kbps
`MBps`	mbps
`GBps`	gbps
`TBps`	tbps
`PBps`	pbps
`°C`	° c
`°c`	° c
`°F`	° f
`°f`	° f

Note: Short abbreviations that are also words or letters (in, min, h, m, A, s) are read as units only when they follow a number.

Words

Abbreviations and spelling

Odi spells all the words in capital letters letter by letter.

Format	Example input	Odi
`[A-Z]…[A-Z]`	`ABC`	a b c
`[A-Z]…[A-Z]`	`JOHN`	j o h n
`[A-Z]<dot>[A-Z]<dot>`	`B.C.`	b c
`[a-z]<dot>[a-z]<dot>`	`e.g.`	for example
`[A-Z]&[A-Z]`	`R&D`	r-n-d

Between capital letters, "&" is read as "n". Between words, "&" is read as "and".

Common abbreviations

Example input	Odi
`Prof.`	professor
`Dr.`	doctor
`etc.`	and so on
`Prof`	prof
`Dr`	dr
`Mr`	mr
`Mrs`	mrs
`Ms`	ms
`Ave`	avenue

Dashed words

Example input	Odi
`E-mail`	e mail
`Paris - Texas`	paris, texas
`Paris-Texas`	paris texas

URLs and e-mails

URLs

Format	Example input	Odi
`(www)<dot>{word}<dot>{domain}`	`www.google.com`	w w w dot google dot com
`http(s)://{word}<dot>{domain}`	`https://google.com`	h t t p s colon double slash google dot com
`http(s)://www<dot>{word}<dot>{domain}`	`https://www.google.com`	h t t p s colon double slash w w w dot google dot com
`(http(s)://)(www)<dot>{word}<dot>{domain}<slash>{sequence}`	`https://www.google.com/news=123`	h t t p s colon double slash w w w dot google dot com slash news equal sign one hundred and twenty three
`(http(s)://)(www)<dot>{non-word}<dot>{domain}`	`www.123.com`	w w w dot one hundred and twenty three dot com

E-mails

Format	Example input	Odi
`{word}@{word}<dot>{domain}`	`info@omilia.com`	i n f o at omilia dot com
`{word}!={symbol}!={number}@{word}<dot>{domain}`	`omilia_19@omilia.com`	omilia underscore one nine at omilia dot com
`{word}!={symbol}!={number}@{word}<dot>{domain}`	`john.smith42@example.com`	john dot smith four two at example dot com
`uppercase{word}@{word}<dot>{domain}`	`SALES@EXAMPLE.COM`	sales at example dot com
`uppercase{word}!={symbol}!={number}@{word}<dot>{domain}`	`FFI.SHDFI.GM@MARRIOTT.COM`	f f i dot s h d f i dot g m at marriott dot com

Note: digits are read one by one, _ reads "underscore", and short code-like parts are spelled letter by letter.

Currency

Format	Example input	Odi
`{symbol}{amount}`	`$25.10`	twenty five dollars and ten cents
`{symbol}{amount}`	`£25.10`	twenty five pounds and ten pence
`{amount}{symbol}`	`25.10€`	twenty five euros and ten cents
`{amount} {code}`	`25 USD`	twenty five u s dollars
`{amount} {quantity} {code}`	`1.3 million USD`	one point three million u s dollars
`{symbol}{amount} {quantity}`	`$1.3 million`	one point three million dollars

Currency codes and symbols

Each reading shows the singular / the plural form. The subdivision is read after "and" when the amount has decimals ("1.01" and "2.50").

Code	Odi	Subdivision
`USD`	u s dollar / u s dollars	cent / cents
`EUR`	euro / euros	cent / cents
`GBP`	pound sterling / pounds sterling	penny / pence
`AUD`	australian dollar / australian dollars	cent / cents
`CAD`	canadian dollar / canadian dollars	cent / cents
`JPY`	japanese yen / japan yen	none: `1.50 JPY` reads one point five japanese yen

Symbol	Odi	Subdivision
`$`	dollar / dollars	cent / cents
`€`	euro / euros	cent / cents
`£`	pound / pounds	penny / pence
`¥` 🆕	japanese yen / japan yen	none

Punctuation and character processing

Supported characters

Char	Description	Used as/in	Odi
`.`	period	sentence end / decimal separator	✅
`,`	comma	sentence break / thousands separator	✅
`-`	dash	number group / minus sign	✅
`@`	at sign	email address	✅
`%`	percent	percentage value, in URLs	✅
`&`	ampersand	"and" (between capital letters it is read as "n")	✅
`$ € £ ¥`	currency signs	part of currency	✅
`=`	equal sign	in URLs	✅
`;`	semicolon	in URLs	✅
`? !`	question mark, exclamation mark	sentence end (see intonation)	✅
`: / ( )`	colon, slash, brackets	time, ratio, URLs, fractions, dates	✅
`° ² ³ " '`	degree, superscripts, quotes	units	✅

Other symbols are read by name in both engines: / "slash", \ "backslash", ^ "caret", _ "underscore", + "plus", # "pound", * "asterisk" and ~ "tilde". Outside URLs a colon or semicolon is replaced by a full stop.

Any other character is removed and does not affect the voice, in both engines. The trademark (™), service mark (℠), registered (®) and copyright (©) signs are removed earlier, by the engine's request pre-processing, before the text reaches the verbalizer. The verbalizer itself does not process them.

Example: Design Hotels™ welcomes you → design hotels welcomes you.

Punctuation intonation

Char	Odi effect
`.`	falling intonation
`?`	rising intonation (en-AU question-type rules: yes/no, wh-, multiple choice)
`,`	falling intonation
`!`	increased intensity
space / dash	short pause (a spaced dash is read as a comma)
no punctuation at the end of a sentence	a period is added automatically