tzdb

This is a list and npm package of:

• "simplified" IANA time zones with their alternative names like Pacific Time instead of America/Los_Angeles, along with major cities for each time zone.
• all existing raw IANA time zones names
• "raw" offsets along with current time offsets
• also includes deprecated time zone names for compatibility

The data and npm packages are automatically updated whenever there are changes to https://www.geonames.org/ which is generated from IANA databases.

This is useful whenever you want to build a time zone select menu in your application.

NPM package

Installation:

1npm add @vvo/tzdb

Usage:

1import { getTimeZones, rawTimeZones, timeZonesNames, abbreviations } from "@vvo/tzdb";

API

getTimeZones()

1const timeZones = getTimeZones();
2
3// You can also provide an optional parameter to include UTC in the result.
4// This adds a time zone with the name "UTC" and a fixed offset of 0.
5const timeZonesWithUtc = getTimeZones({ includeUtc: true });

This method returns an array of time zones objects:

1[
2  // ...
3  {
4    name: "America/Los_Angeles",
5    alternativeName: "Pacific Time",
6    group: ["America/Los_Angeles"],
7    continentCode: "NA",
8    continentName: "North America",
9    countryName: "United States",
10    countryCode: "US",
11    mainCities: ["Los Angeles", "San Diego", "San Jose", "San Francisco"],
12    rawOffsetInMinutes: -480,
13    abbreviation: "PST",
14    rawFormat: "-08:00 Pacific Time - Los Angeles, San Diego, San Jose, San Francisco",
15    currentTimeOffsetInMinutes: -420, // "current" time zone offset, this is why getTimeZones() is a method and not just an object: it works at runtime
16    currentTimeFormat: "-07:00 Pacific Time - Los Angeles, San Diego",
17  },
18  // ...
19];

When relevant, time zones are grouped. The rules for grouping are:

• if the time zones are in the same country
• if the DST or summer time offsets are the same
• if the non-DST, non-summer time offsets are the same
• then we group the time zones
• the "main" time zone name (name attribute), is always the one from the most populated city

Here's a grouping example:

1{
2  name: "America/Dawson_Creek",
3  alternativeName: "Mountain Time",
4  group: ["America/Creston", "America/Dawson_Creek", "America/Fort_Nelson"],
5  continentCode: "NA",
6  continentName: "North America",
7  countryName: "Canada",
8  countryCode: "CA",
9  mainCities: ["Fort St. John", "Creston", "Fort Nelson"],
10  rawOffsetInMinutes: -420,
11  abbreviation: "MST",
12  rawFormat: "-07:00 Mountain Time - Fort St. John, Creston, Fort Nelson",
13  currentTimeOffsetInMinutes: -420,
14  currentTimeFormat: "-07:00 Mountain Time - Fort St. John, Creston"
15}

rawTimeZones

This is an array of time zone objects without the current time information:

1[
2  // ...
3  {
4    name: "America/Los_Angeles",
5    alternativeName: "Pacific Time",
6    group: ["America/Los_Angeles"],
7    continentCode: "NA",
8    continentName: "North America",
9    countryName: "United States",
10    countryCode: "US",
11    mainCities: ["Los Angeles", "San Diego", "San Jose", "San Francisco"],
12    rawOffsetInMinutes: -480,
13    abbreviation: "PST",
14    rawFormat: "-08:00 Pacific Time - Los Angeles, San Diego, San Jose, San Francisco",
15  },
16  // ...
17];

timeZonesNames

This is an array of time zone names:

1[
2  // ...
3  "America/Juneau",
4  "America/Kentucky/Louisville",
5  "America/Kentucky/Monticello",
6  "America/Kralendijk",
7  "America/La_Paz",
8  "America/Lima",
9  "America/Los_Angeles",
10  "America/Lower_Princes",
11  "America/Maceio",
12  "America/Managua",
13  "America/Manaus",
14  "America/Marigot",
15  "America/Martinique",
16  "America/Matamoros",
17  // ...
18];

abbreviations

This is an object mapping timezone abbreviations to their full forms:

1{
2  // ...
3  "Australian Central Daylight Time": "ACDT",
4  "Australian Central Standard Time": "ACST",
5  "Australian Central Time": "ACT",
6  "Australian Central Western Standard Time": "ACWST",
7  "Australian Eastern Daylight Time": "AEDT",
8  "Australian Eastern Standard Time": "AEST",
9  "Australian Eastern Time": "AET",
10  "Australian Western Daylight Time": "AWDT",
11  "Australian Western Standard Time": "AWST",
12  "Azerbaijan Summer Time": "AZST",
13  "Azerbaijan Time": "AZT",
14  "Azores Summer Time": "AZOST",
15  "Azores Time": "AZOT",
16  "Bangladesh Standard Time": "BST",
17  "Bhutan Time": "BTT",
18  "Bolivia Time": "BOT",
19  // ...
20};

Caution: Although abbreviations can be easy to lookup, they can be misleading. For example: CST can refer to Central Standard Time (-06.00 UTC), China Standard Time (+06.00 UTC) or Cuba Standard Time (-05.00 UTC). And abbreviation full forms don't directly map to any property in the time zone objects returned by rawTimeZones or getTimeZones().

Notes

• We provide two cities when grouping happens, ranked by population
• We provide alternative names ("Pacific Time" for "America/Los_Angeles") and remove "Standard", "Daylight" or "Summer" from them
• If you're using this to build a time zone selector and saving to a database then:
  • make sure to save the name attribute (America/Los_Angeles) in your database
  • when displaying the select with a default value from your database, either select the time zone name that matches, or if the time zone name is part of the group. Example:

1const value = timeZones.find((timeZone) => {
2  return dbData.timeZone === timeZone.name || timeZone.group.includes(dbData.timeZone);
3});