localized-dst

Determine if a date is in daylight savings time by country/state/city

Usage no npm install needed!

<script type="module">
  import localizedDst from 'https://cdn.skypack.dev/localized-dst';
</script>

README

localized DST

Determine if a date is in daylight savings time by country/state/city

Motivation

I wasn't able to find a correct library to do the simple task is my date during DST (Daylight Savings Time. Every library was old or unconstistant because I learnt the hard way but not every Country/State/City have the same DST...

This is based on the information of https://www.timeanddate.com/time/dst/

Installation

npm install localized-dst

How to use it

import { isDst } from 'localized-dst';

// DST info for Canada, Québec, Montréal
console.log(
  isDst(new Date('2019-08-14 21:00:00'), {
    location: 'CAN.QUEBEC.MONTREAL'
  })
);
// return true

// DST info for France (Paris)
console.log(
  isDst(new Date('2019-11-28 21:00:00'), {
    location: 'FRA'
  })
);
// return false

Implemented DST data

Country State City Key Years
Canada Quebec Montreal CAN.QUEBEC.MONTREAL 2000-2030
Ontario Toronto CAN.ONTARIO.TORONTO 2000-2030
France Metropole Paris FRA.METROPOLE.PARIS 2000-2030
USA HAWAI USA.HAWAI all

How to participate

If you think something is missing or corrupted, please submit a PR to this repo!

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