Put a nonbreaking space (` `) between the number and the unit.

## Spaces in units of measurement

For most units of measurement, when you specify a number with the unit, use a
nonbreaking space between the number and the unit. This guidance applies in both
HTML and Markdown.

For guidance about when to spell out units, see the
[Abbreviations](https://developers.google.com/style/abbreviations#spelling-out) page.

For guidance about whether to hyphenate, see the [Hyphens](https://developers.google.com/style/hyphens#compounds)
page.
Recommended: `64 GB` (64 GB)

Recommended: `25 mm` (25 mm)

Recommended: a 128-bit system

Not recommended: `64 GB`

Not recommended: 64GB

For more information about making abbreviations plural, see [Plural abbreviations](https://developers.google.com/style/pluralization#making-abbreviations-plural).

However, when the unit of measure is money or percent or degrees of an angle,
don't use a space. For more information, see [Currency](https://developers.google.com/style/units-of-measure#currency).
Recommended: $10

Recommended: £25

Recommended: 65%

Recommended: 180°

For degrees of temperature, include a nonbreaking space between the number and the degree symbol.
Don't use a space between the degree symbol (`°`) and the temperature scale
(*F* or *C*).

### Example

50 °C

### HTML

`50 °C`

### Markdown

`50 °C`

For Kelvin temperatures, leave out the degree symbol but use a nonbreaking space before the
*K*.

### Example

300 K

### HTML

`300 K`

### Markdown

`300 K`

When a number and unit of measurement combine to modify a noun, don't hyphenate unless
the hyphen is needed for clarity.

Recommended:
`200 GB disk` (200 GB disk)

## Ranges of numbers with units

In a range of numbers, repeat the unit for each number. *Unit* includes both symbols (like
the degree symbol (º)) and abbreviations (like *MB* for megabytes) but not nouns
(like *file*). For more information, see
[Range of numbers](https://developers.google.com/style/hyphens#number-range).

Use the word *to* between the numbers, rather than a hyphen. A hyphen
can be misinterpreted as a subtraction sign.
Recommended: -40 °C to 85 °C

Not recommended: -40-85 °C

## Hyphens with multiplied units

When the components of a unit of measurement are multiplied by each other,
hyphenate them.

Recommended: 5 vCPU-hours

Recommended: 40 person-hours

## Use *k* to indicate thousands

In some contexts, it might be appropriate to indicate thousands of something by
following a number with a lowercase *k*. If you do that, then follow these
guidelines:

- Don't put a space between the number and *k*.
- Add a noun to indicate what the number measures, and to make clear that you're not using *k* as an abbreviation for *kilobytes*.

Recommended: On this plan, you are
limited to 55k download operations and 20k upload operations per day.

## Currency

If you're writing about monetary amounts, make sure that the reader knows what
currency you're referring to. For example, the dollar sign---the *$*
symbol---can refer to US dollars, Canadian dollars, Mexican pesos, and several
other currencies.

If there's any possibility of ambiguity, use a currency indicator before
the amount. For details, see section 9.20 and following in the Chicago Manual of Style, 17th edition.

Recommended: US$10

## Rates

Use *per* instead of the division slash (/) when space permits.
It's OK to use the division slash when space is limited,
such as in a table with small cells.

Shorten *per* to *p* only for well-established abbreviations for
rate units, such as *Gbps* for *gigabits per second* or
*MBps* for *megabytes per second*.

Recommended: requests per day

Not recommended: requests/day

Recommended: Gbps

Not recommended: Gb/s

## Decimal and binary units

Use the same system to measure bytes as the technology that you're documenting.
Don't use *MB* if you mean *MiB*, or *GB* if you mean *GiB*. The following
table lists common types of
[decimal and binary units](https://en.wikipedia.org/wiki/Byte#Multiple-byte_units):

| Decimal units | Binary units |
|---|---|
| kB (kilobyte, or 1000 bytes) | KiB (kibibyte, or 1024 bytes) |
| MB (megabyte, or 1000^2^ bytes) | MiB (mebibyte, or 1024^2^ bytes) |
| GB (gigabyte, or 1000^3^ bytes) | GiB (gibibyte, or 1024^3^ bytes) |

For more information about abbreviating measurement terms, see
[When to spell out a term](https://developers.google.com/style/abbreviations#spelling-out).

## More resources

- [Mathematical notation](https://developers.google.com/style/mathematical-notation)
- [Numbers](https://developers.google.com/style/numbers)