Bytes utility

Utility to parse a string bytes (ex: 1TB) to bytes (1,000,000,000,000) and vice-versa.

This uses the byte units defined in ISO/IEC 80000-13:2008, both the binary prefixes and the original SI units.

This is a fork of the bytes module, except:

• It uses IEC units by default
• Supports a wider range of units
• Supports changing to compatability (JEDEC) mode, and formatting in whichever prefix type you prefix (binary, metric, compatibility)

Supported Units

Supported units and abbreviations are as follows and are case-insensitive:

Metric/Decimal Prefixes

| Value | Abbr | Name | | ---------------- | ---- | --------- | | 1 | B | byte | | 10001 | kB | kilobyte | | 10002 | MB | megabyte | | 10003 | GB | gigabyte | | 10004 | TB | terabyte | | 10005 | PB | petabyte | | 10006 | EB | exabyte | | 10007 | ZB | zettabyte | | 10008 | YB | yottabyte |

Binary Prefixes:

| Value | Abbr | Name | | ---------------- | ---- | --------- | | 1 | B | byte | | 10241 | KiB | kibibyte | | 10242 | MiB | mebibyte | | 10243 | GiB | gibibyte | | 10244 | TiB | tebibyte | | 10245 | PiB | pebibyte | | 10246 | EiB | exbibyte | | 10247 | ZiB | zebibite | | 10248 | YiB | yobibite |

Compatibility Binary Prefixes (JEDEC)

Overwrites the lower units of the metric system with the commonly misused prefixes

| Value | Abbr | Name | | ---------------- | ---- | --------- | | 10001 | kB | kilobyte | | 10002 | MB | megabyte | | 10003 | GB | gigabyte | | 10004 | TB | terabyte |

Installation

This is a Node.js module available through the npm registry. Installation is done using the npm install command:

npm install bytes-iec

Usage

var bytes = require('bytes');

bytes.format(number value, [options]): string|null

Format the given value in bytes into a string. If the value is negative, it is kept as such. If it is a float, it is rounded.

It supports the following output formats:

• binary: uses the binary prefixes (KiB, MiB...)
• decimal|metric: uses the metric system (decimal) prefixes (kB, MB...)
• compatibility: uses the binary units, but the metric prefixes (kB == 1024B, MB...)

Arguments

| Name | Type | Description | |---------|----------|--------------------| | value | number | Value in bytes | | options | Object | Conversion options |

Options

| Property | Type | Description | |-------------------|--------|-----------------------------------------------------------------------------------------| | decimalPlaces | number｜null | Maximum number of decimal places to include in output. Default value to 2. | | fixedDecimals | boolean｜null | Whether to always display the maximum number of decimal places. Default value to false | | thousandsSeparator | string｜null | Example of values: ' ', ',' and .... Default value to ''. | | unit | string｜null | The unit in which the result will be returned (B/KB/MB/GB/TB). Default value to '' (which means auto detect). | | unitSeparator | string｜null | Separator to use between number and unit. Default value to ''. | | mode | string&124;null | Which format to output: binary, metric, decimal, compatibility. Default value is metric |

Returns

| Name | Type | Description | |---------|------------------|-------------------------------------------------| | results | string｜null | Return null upon error. String value otherwise. |

Example

bytes(1000);
// output: '1kB'

bytes(1000, {thousandsSeparator: ' '});
// output: '1 000B'

bytes(1024);
// output: '1.02kB'

bytes(1024 * 1.7, {decimalPlaces: 0});
// output: '2KB'

bytes(1000, {unitSeparator: ' '});
// output: '1 kB'

bytes(2048, {mode: 'binary'});
// output: '2 KiB'

bytes(1024 * 1024 * 2, {unit: 'KiB'});
// output: '2048 KiB'

bytes(1024 * 1024 * 2, {unit: 'KB'});
// output: '2097.152 KB'

bytes(1024 * 1024 * 2, {unit: 'KB', mode: 'compatibility'});
// output: '2048 KB'

bytes.parse(string｜number value): number｜null

Parse the string value into an integer in bytes. If no unit is given, or value is a number, it is assumed the value is in bytes.

If the unit given has partial bytes, they are dropped (rounded down).

Arguments

| Name | Type | Description | |---------------|--------|--------------------| | value | string｜number | String to parse, or number in bytes. | | options | Object | Conversion options |

| Property | Type | Description | | -------------------- | --------------------- | ----------- | | mode | string|null | Which mode to use (see bytes.format) |

Returns

| Name | Type | Description | |---------|-------------|-------------------------| | results | number｜null | Return null upon error. Value in bytes otherwise. |

Example

bytes('1kB');
// output: 1024

bytes('1024');
// output: 1024

bytes('1.0001 kB');
// output: 1000
bytes('1.0001 KiB');
// output: 1024

bytes('1kB', {mode: compatibility});
// output: 1024

bytes.withDefaultMode(string mode): object

Returns a new module which acts like the bytes module, except with the given mode as the default.

Arguments

| Name | Type | Description | |---------------|----------|--------------------| | mode | string | Default mode to use |

Returns

| Name | Type | Description | |---------|-------------|-------------------------| | results | object | Returns the byte.js module, with a default mode |

Example

var bytes = require('bytes').withDefaultMode('compatibility');

bytes('1kB');
// output: 1024

bytes('1KiB');
// output: 1024

bytes(1024);
// output: 1 kB

bytes(1024, {mode: 'metric'});
// output: 1.02kB

bytes('1kB', {mode: 'metric'});
// output: 1000

License

MIT