fast-date-format

fast-date-format is significantly faster than other date formatting modules.

Installation

npm install fast-date-format

Example

import { DateFormatter } from 'fast-date-format';

const dateFormat = new DateFormatter('YYYYMMDD');

dateFormat.format();
dateFormat.format(new Date());

Escaping

To escape characters in a format, surround the characters with square brackets.

const dateFormat = new DateFormatter('[Month: ]MMMM');

dateFormat.format(); // Month: December

Tokens

Supported formatting tokens:

| Token | Example | Description | | ------------- | ------------------ |---------------------- | | YYYY | 2018 | Year | | YY | 18 | 2 Digit Year | | MMMM | January..December| Month name | | MMM | Jan..Dec | 3 letter month name | | MM | 01..12 | Month | | M | 1..12 | Month | | HH | 00..23 | Hours (24 hour time) | | H | 0..23 | Hours (24 hour time) | | hh | 01..12 | Hours (12 hour time) | | h | 1..12 | Hours (12 hour time) | | kk | 01..24 | Hours (24 hour time) | | k | 1..24 | Hours (24 hour time) | | A | am, pm | Post or ante meridiem | | dddd | Monday..Sunday | Day name | | ddd | Mon..Sun | 3 letter day name | | DDDD | 001..365 | Day of year | | DDD | 1..365 | Day of year | | DD | 01..31 | Day of month | | D | 1..31 | Day of month | | E | 1..7 | Day of week | | m | 0..59 | Minutes | | mm | 00..59 | Minutes | | s | 0..59 | Seconds | | ss | 00..59 | Seconds | | SSS | 000..999 | Milliseconds | | ZZ | -02:00 | Offset from UTC | | Z | -0200 | Offset from UTC | | x | 1528643900952 | Unix timestamp in ms |

API

DateFormatter(options)

Creates a new date formatter.

options

Either a date format as a string or an object with the following properties:

dateFormat

A date format as a string.

cache (optional)

Enables caching to increase formatting speed if set to true. Defaults to false.

DateFormatter#format([date])

Formats the date according to the dateFormat. If no date is passed the current date is used.

DateFormatter#addLocale(language, data)

Adds translations for the names of months and weekdays.

dateFormat.addLocale('en', {
  weekdays: ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday'],
  months: ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December']
})

Three letter abbreviations of the names are being generated from the months and weekdays.

DateFormatter#setLocale(language)

Changes the locale of the DateFormat instace to language. Build-in languages: en, de & it.

dateFormat.setLocale('en')

Benchmark

The benchmark has been run with Node.js v24.2.0.

$ node benchmark/benchmark.js
moment x 1,063,970 ops/sec ±0.76% (90 runs sampled)
date-format x 1,209,666 ops/sec ±0.29% (96 runs sampled)
dateformat x 557,058 ops/sec ±0.36% (95 runs sampled)
fast-date-format x 10,317,337 ops/sec ±0.41% (97 runs sampled)
fecha x 740,233 ops/sec ±0.82% (52 runs sampled)
speed-date x 9,729,244 ops/sec ±0.47% (97 runs sampled)
date-fns x 417,645 ops/sec ±0.33% (92 runs sampled)
Fastest is fast-date-format

With activated cache option:

$ node benchmark/benchmarkCache.js
moment x 1,411,803 ops/sec ±0.51% (99 runs sampled)
date-format x 1,686,897 ops/sec ±0.28% (81 runs sampled)
dateformat x 822,427 ops/sec ±0.90% (96 runs sampled)
fast-date-format x 14,652,810 ops/sec ±0.40% (95 runs sampled)
fecha x 972,796 ops/sec ±0.34% (99 runs sampled)
speed-date x 13,002,381 ops/sec ±0.43% (95 runs sampled)
date-fns x 587,636 ops/sec ±0.31% (100 runs sampled)
Fastest is fast-date-format

License

MIT