Numbers

In general text, write the numbers one to nine in words, and the numbers 10 and above in figures. The only exception is when there are multiple numbers, varying from numbers below and above 10, used in one sentence.
In this case, use words. For example, there were fifteen people separated into three groups of five.
Exceptions include:

• Addresses, where street numbers accompany the street name
• Fractions
• Specific technical terminology, for example 2-pole device
• Measurements
• Money, for example $9.70
• Percentages
• Postcodes
• Numbers from zero to nine appearing in a list with bigger numbers, then they should all be presented numerically (for example, from 6 to 45 students, between 5 and 15 minutes).

In relation to measurements, use numerals in tables and for numbers accompanied by a symbol or a unit of measurement. Note a space is required between a numeral and a symbol of measurement, apart from the symbol for degree (angle), minute and second. For example, 10 mL, 100 g, 500 kg, 20 mm, 45 °C (temperature), 45° (degree of plane angle).

In relation to percentages, Note: Use the symbol % when using numerals, use per cent with either words or numerals. Per cent in text is two words. In documents where numerals are generally being employed for numbers, it is preferable also to show percentages in numerals with the symbol. For example, 54 per cent in text, 54% in tables or where numerals are being used for numbers. Do not use a space between a numeral and the symbol.

Use digits for numbers greater than nine except when the number starts a sentence, then it must always be in words.
For example, one hundred and thirty-two people were affected by the storm.

Use commas to divide figures into three-digit blocks. This is so that screen readers interpret the number correctly, rather than as separate numbers. For example, 5,000 teachers, $10,000.
Use commas to break up numbers of five digits or more. For example, 200, 5000, 12,345, 123,456, 1,234,567, 12,345,678.

Use hyphens to connect numbers defining ages coupled with the words year-old. For example, 25-year-old, 25- to 75-year-olds.
Generalised or approximate numbers are usually written in words. For example, at least five thousand; one million voters.

Write unit names in full when they are used on their own. For example, measure the distance in metres.
Large or more complex numbers should use a combination of words and numerals, for example 2.5 million. Use the term billion to mean 1000 million.
Telephone numbers should appear as follows.
For example:

• (07) 4321 6789
• 0408 123 456
• 1800 123 456
• 61 7 3237 1934.

When using number spans, limit the number of digits in the second part of the span. For example, 9–12, 40–1, 402–5, 440–553.
But use full digits in these examples, 11–12, 11–19.
For a span of years say 1998–99 or 1998–2001.