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Numbers, measurements, dates and time

On this page

  • Numbers
  • Measurements
  • Dates
  • Time
  • Ranges of numbers, dates and time
  • Fractions and percentages
  • Statistics

Numbers

Numerals (1, 2, 3 and so on)

We use numerals for all numbers (including 1 to 2). People find numerals easier to read and they scan for them.

For numbers over 999, use a comma for clarity - for example, 1,000.

For numbers less than 1, use 0 before the decimal point - for example, 0.25.

Examples of where we use numerals

  • Add 1 to 2 teaspoons of honey.
  • It takes 1 to 3 weeks from the time you were exposed to chickenpox for the spots to start appearing.
  • Do this for 1 or 2 minutes.
  • Depression affects about 1 in 10 people at some point during their life.
At the start of a sentence

It is OK to use numbers at the start of a sentence but, if it looks confusing, consider rewording your sentence.

Example: 14 units is equivalent to 6 pints of average-strength beer or 10 small glasses of low-strength wine.

In headings

Examples:

  • 8 tips for healthy eating
  • 6-in-1 vaccine
In lists

Example: "A portion is:

  • 80g of fresh, canned or frozen fruit and vegetables
  • 30g of dried fruit
  • 150ml glass of fruit juice or smoothie"

Examples of where we do not use numerals

We do not use numerals in some medicines information about dosage because we've found they can be confusing.

Ordinal numbers (1st, 2nd, 3rd and so on)

We use numerals with letter suffixes for ordinal numbers, for example "1st", as in "your 1st visit".

Do not use superscript. It does not always read out correctly on screen readers and could confuse people.

Measurements

Dosage

We do not use a space between amount and measurement.

Example: The usual dose is 250mg to 500mg.

Use your judgement when explaining medicines doses. Avoid having 2 sets of numerals next to each other.

We say: We do not say:
The usual dose is one or two 200mg tablets 3 times a day. The usual dose is 1 or 2 200mg tablets 3 times a day.

Temperature

We use Celsius for temperature.

Example: a temperature of 38C or higher.

Read more about temperature in the A to Z of NHS health writing.

Metric and imperial

We generally use metric. If it's helpful, add imperial in brackets, for example, for advice on cutting back on alcohol.

Do not use imperial for medicines dosage or infant feeding.

Dates

We use this format: 6 August 2018.

As far as possible, spell out months in full. Screen readers read out shortened months (Jan, Feb and so on) in inconsistent and sometimes confusing ways.

Time

TBD
We use: We do not use:
5.30pm 1730hrs
midnight 00:00, 12am
midday 12 noon, 12pm
6 hours 30 minutes 6.5hrs

Ranges of numbers, dates and time

We use "to" for time, date and numerical ranges, not hyphens or dashes.

Examples:

  • The surgery is open Monday to Friday, 2pm to 6pm.
  • A BMI of 18.5 to 24.9 means you're a healthy weight.

Fractions and percentages

Spell out common fractions like two-thirds.

For percentages, use the % symbol - for example, 50%. However, it's often better not to use a percentage. Instead of 50%, for example, you could say "1 in 2" or "half".

Statistics

Use statistics sparingly. Consider the style of writing and your target audience. For example, readers of Behind the Headlines, the Health A to Z and Live Well on the NHS website will have different needs.

Use the clearest, most meaningful format to explain what you're illustrating. For example, use "1 in 7 people" rather than "14.3% of people".

Avoid mixing different number formats. Use one or the other.

Example: Overall, around 7 in every 10 people live at least a year after diagnosis and around 5 in 10 people live at least 10 years.

Updated: August 2019