• Convert dates between any timezone supported by the system.
• Parses ISO8601 time strings.
• MIT licensed, use the library any way you want. For real.
• Minimal (less than 2 KB minified), no dependencies. Relies on JavaScript Intl and current best practices.
• Works in Node.js >=14.0 (both require and import).
• Works in Deno >=1.8.
• Works in Bun >=0.2.2
• Works in browsers as standalone, UMD or ES-module.
• Includes TypeScript typings.

Try it live on jsfiddle

Converting a Date object to another timezone in JavaScript is possible using the Intl feature of vanilla JS.

// Get current time in Asia/Tokyo, using vanilla js
new Date().toLocaleString("sv-SE", { timeZone: "Asia/Tokyo" });
// -> 2022-09-15 17:23:45

However - if you want to convert date/time from another timezone, or convert between different timezones, things get trickier.

Minitz is a minimal library built to solve the problem in the simplest possible way, and made to work in all environments (Node/Deno/Browser, ESM/UMD/CommonJS).

Simple examples of conversion from a remote timezone, and a conversion between different timezones.

// Get local time from time in Asia/Tokyo, using minitz and vanilla js
const localTime = minitz(2022,9,15,23,0,0,"Asia/Tokyo")
console.log( localTime.toLocaleString("sv-SE") );
// -> 2022-09-15 16:00:00

// Get time in America/New_York from time in Asia/Tokyo, using minitz and vanilla js
// Also demonstrates that it's possible to use ISO8601 strings as input to minitz, through `.fromTZISO`
const localTime = minitz.fromTZISO("2022-09-15 23:00:00","Asia/Tokyo");
console.log( localTime.toLocaleString("sv-SE", { timeZone: "America/New_York" }) );
// -> 2022-09-15 10:00:00

More examples are available further below, and the full documentation is available at hexagon.github.io/minitz.

npm install minitz --save

JavaScript

// ESM Import ...
import minitz from "minitz";

// ... or CommonJS Require
const minitz = require("minitz");

TypeScript

Note that only default export is available in Node.js TypeScript, as the commonjs module is used internally.

import minitz from "minitz";

// ...

JavaScript

import minitz from "https://deno.land/x/[email protected]/src/minitz.js";

// ...

TypeScript

import { minitz } from "https://deno.land/x/[email protected]/src/minitz.js";

// ...

Check https://deno.land/x/minitz for latest available version

bun add minitz

Note If you experience problems during install, try using bun add minitz --backend=copyfile.

JavaScript

import minitz from "minitz";

• Download the latest zipball
• Extract
• Grab minitz.min.js (UMD and standalone) or minitz.min.mjs (ES-module) from the dist/ folder

To use as an UMD-module (stand alone, RequireJS etc.)

<script src="https://cdn.jsdelivr.net/npm/minitz/dist/minitz.min.js"></script>

To use as an ES-module

<script type="module">
	import minitz from "https://cdn.jsdelivr.net/npm/minitz/dist/minitz.min.mjs";

	// ... see usage section ...
</script>

The examples below will work only if you have imported minitz as described in the 'Installation' section. If that's not the case the results may vary.

Standard way

// Convert 2022-09-10 23:08:09 in New York to local time (in this example Europe/Stockholm)
console.log("Local time: ", minitz(2022, 9, 10, 23, 8, 9, "America/New_York").toLocaleString("sv-SE"));
// Local time:  2022-09-11 05:08:09

Providing an ISO8601 timestring

// Convert 2022-09-10 23:08:09 in New York to local time (in this example Europe/Stockholm)
console.log("Local time: ", minitz("2022-09-10 23:08:99", "America/New_York").toLocaleString("sv-SE"));
// Local time:  2022-09-11 05:08:09

Provided that you only need to display the result, converting local time to specific timezone is best achieved with vanilla JavaScript.

console.log("Time in New York printed with system locale: ", new Date().toLocaleString("sv-SE", { timeZone: "America/New_York"}));
// -> Time in New York printed with system locale:  2022-09-14 17:29:42

If you need to use the result in any other way, it's better to use minitz to convert to a remote timezone. This way you'll get the results as an object, which also includes the timezone to which the time is converted to.

//  Convert to local time to time in America/New_York
//  As time in other timezones than local cannot be represented correctly by a date object
//  a generic object is returned
console.log("Time in New York: ", minitz.toTZ(new Date(), "America/New_York"));
// -> Time in New York:
//  {
//     y: 2022,
//     m: 9,
//     d: 14,
//     h: 17,
//     i: 29,
//     s: 42,
//     tz: 'America/New_York'
//  }

Any contributions are welcome. See Contribution Guide

MIT