Module | ActionView::Helpers::NumberHelper
In: | lib/action_view/helpers/number_helper.rb

Provides methods for converting numbers into formatted strings. Methods are provided for phone numbers, currency, percentage, precision, positional notation, and file size.

### Methods

number_to_currency number_to_human_size number_to_percentage number_to_phone number_with_delimiter number_with_precision

### Constants

STORAGE_UNITS | = | %w( Bytes KB MB GB TB ).freeze

### Public Instance methods

number_to_currency(number, options = {})

Formats a `number` into a currency string (e.g., $13.65). You can customize the format in the `options` hash.

#### Options

- `:precision` - Sets the level of precision (defaults to 2).
- `:unit` - Sets the denomination of the currency (defaults to "$").
- `:separator` - Sets the separator between the units (defaults to ".").
- `:delimiter` - Sets the thousands delimiter (defaults to ",").
- `:format` - Sets the format of the output string (defaults to "%u%n"). The field types are:

        %u  The currency unit
        %n  The number

#### Examples

     number_to_currency(1234567890.50)                    # => $1,234,567,890.50
     number_to_currency(1234567890.506)                   # => $1,234,567,890.51
     number_to_currency(1234567890.506, :precision => 3)  # => $1,234,567,890.506

     number_to_currency(1234567890.50, :unit => "&pound;", :separator => ",", :delimiter => "")
     # => &pound;1234567890,50
     number_to_currency(1234567890.50, :unit => "&pound;", :separator => ",", :delimiter => "", :format => "%n %u")
     # => 1234567890,50 &pound;

number_to_human_size(number, *args)

Formats the bytes in `size` into a more understandable representation (e.g., giving it 1500 yields 1.5 KB). This method is useful for reporting file sizes to users. This method returns nil if `size` cannot be converted into a number. You can customize the format in the `options` hash.

#### Options

- `:precision` - Sets the level of precision (defaults to 1).
- `:separator` - Sets the separator between the units (defaults to ".").
- `:delimiter` - Sets the thousands delimiter (defaults to "").

#### Examples

     number_to_human_size(123)                                          # => 123 Bytes
     number_to_human_size(1234)                                         # => 1.2 KB
     number_to_human_size(12345)                                        # => 12.1 KB
     number_to_human_size(1234567)                                      # => 1.2 MB
     number_to_human_size(1234567890)                                   # => 1.1 GB
     number_to_human_size(1234567890123)                                # => 1.1 TB
     number_to_human_size(1234567, :precision => 2)                     # => 1.18 MB
     number_to_human_size(483989, :precision => 0)                      # => 473 KB
     number_to_human_size(1234567, :precision => 2, :separator => ',')  # => 1,18 MB

You can still use `number_to_human_size` with the old API that accepts the `precision` as its optional second parameter:

     number_to_human_size(1234567, 2)    # => 1.18 MB
     number_to_human_size(483989, 0)     # => 473 KB

number_to_percentage(number, options = {})

Formats a `number` as a percentage string (e.g., 65%). You can customize the format in the `options` hash.

#### Options

- `:precision` - Sets the level of precision (defaults to 3).
- `:separator` - Sets the separator between the units (defaults to ".").
- `:delimiter` - Sets the thousands delimiter (defaults to "").

#### Examples

     number_to_percentage(100)                                        # => 100.000%
     number_to_percentage(100, :precision => 0)                       # => 100%
     number_to_percentage(1000, :delimiter => '.', :separator => ',') # => 1.000,000%
     number_to_percentage(302.24398923423, :precision => 5)           # => 302.24399%

number_to_phone(number, options = {})

Formats a `number` into a US phone number (e.g., (555) 123-9876). You can customize the format in the `options` hash.

#### Options

- `:area_code` - Adds parentheses around the area code.
- `:delimiter` - Specifies the delimiter to use (defaults to "-").
- `:extension` - Specifies an extension to add to the end of the generated number.
- `:country_code` - Sets the country code for the phone number.

#### Examples

     number_to_phone(1235551234)                                        # => 123-555-1234
     number_to_phone(1235551234, :area_code => true)                    # => (123) 555-1234
     number_to_phone(1235551234, :delimiter => " ")                     # => 123 555 1234
     number_to_phone(1235551234, :area_code => true, :extension => 555) # => (123) 555-1234 x 555
     number_to_phone(1235551234, :country_code => 1)                    # => +1-123-555-1234

     number_to_phone(1235551234, :country_code => 1, :extension => 1343, :delimiter => ".")
     => +1.123.555.1234 x 1343

number_with_delimiter(number, *args)

Formats a `number` with grouped thousands using `delimiter` (e.g., 12,324). You can customize the format in the `options` hash.

#### Options

- `:delimiter` - Sets the thousands delimiter (defaults to ",").
- `:separator` - Sets the separator between the units (defaults to ".").

#### Examples

     number_with_delimiter(12345678)                        # => 12,345,678
     number_with_delimiter(12345678.05)                     # => 12,345,678.05
     number_with_delimiter(12345678, :delimiter => ".")     # => 12.345.678
     number_with_delimiter(12345678, :seperator => ",")     # => 12,345,678
     number_with_delimiter(98765432.98, :delimiter => " ", :separator => ",")
     # => 98 765 432,98

You can still use `number_with_delimiter` with the old API that accepts the `delimiter` as its optional second and the `separator` as its optional third parameter:

     number_with_delimiter(12345678, " ")                     # => 12 345.678
     number_with_delimiter(12345678.05, ".", ",")             # => 12.345.678,05

number_with_precision(number, *args)

Formats a `number` with the specified level of `:precision` (e.g., 112.32 has a precision of 2). You can customize the format in the `options` hash.

#### Options

- `:precision` - Sets the level of precision (defaults to 3).
- `:separator` - Sets the separator between the units (defaults to ".").
- `:delimiter` - Sets the thousands delimiter (defaults to "").

#### Examples

     number_with_precision(111.2345)                    # => 111.235
     number_with_precision(111.2345, :precision => 2)   # => 111.23
     number_with_precision(13, :precision => 5)         # => 13.00000
     number_with_precision(389.32314, :precision => 0)  # => 389
     number_with_precision(1111.2345, :precision => 2, :separator => ',', :delimiter => '.')
     # => 1.111,23

You can still use `number_with_precision` with the old API that accepts the `precision` as its optional second parameter:

      number_with_precision(number_with_precision(111.2345, 2)   # => 111.23

[Validate]