Fast-date-format NPM

fast-date-format

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

Installation

npm install fast-date-format

Example

const DateFormat = require('fast-date-format');

const dateFormat = new DateFormat('YYYYMMDD');

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

Escaping

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

const dateFormat = new DateFormat('[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

DateFormat(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.

DateFormat#format(date)

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

DateFormat#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.

DateFormat#setLocale(language)

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

dateFormat.addLocale('en')

Benchmark

The benchmark has been run with Node.js v10.16.3.

$ node benchmark/benchmark.js
moment x 268,396 ops/sec ±0.87% (88 runs sampled)
date-format x 380,505 ops/sec ±0.42% (91 runs sampled)
dateformat x 99,375 ops/sec ±0.91% (87 runs sampled)
fast-date-format x 1,116,499 ops/sec ±0.57% (86 runs sampled)
fecha x 230,543 ops/sec ±0.93% (93 runs sampled)
speed-date x 1,083,871 ops/sec ±0.65% (91 runs sampled)
date-fns x 101,370 ops/sec ±1.18% (89 runs sampled)
Fastest is fast-date-format

With activated cache option:

$ node benchmark/benchmarkCache.js
moment x 356,945 ops/sec ±0.92% (84 runs sampled)
date-format x 404,826 ops/sec ±0.63% (86 runs sampled)
dateformat x 111,103 ops/sec ±1.03% (86 runs sampled)
fast-date-format x 2,618,465 ops/sec ±0.90% (90 runs sampled)
fecha x 306,050 ops/sec ±0.51% (91 runs sampled)
speed-date x 1,950,085 ops/sec ±0.82% (86 runs sampled)
date-fns x 150,776 ops/sec ±0.47% (88 runs sampled)
Fastest is fast-date-format