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Create ICS files in ES6. Works in Node.js or in the browser.


npm version Build Status js-standard-style


npm install --save ics-js



View documentation on ESDoc.

Quick Guide

Import the module:

import * as ICS from 'ics-js';

Or import just what is needed:

import { VCALENDAR, VEVENT } from 'ics-js';

Create a component

const cal = new ICS.VCALENDAR();

The following components are implenented:

Add properties to a component

 * Component#addProp(name, value, props = {}, skipTransformer = false)
 * @param {string} name - Name of the property (e.g. DTSTAMP).
 * @param {*} [value] - Value of the property.
 * @param {Object} [props={}] - Object of properties for the property. Object keys and values are directly injected.
 * @param {boolean} [skipTransformer=false] - Explicitly determine if the property's value is transformed.

cal.addProp('VERSION', 2) // Number(2) is converted to '2.0'
cal.addProp('PRODID', 'XYZ Corp');

Each component contains a list of property validations. Only valid properties can be added according to the RFC 5545 spec.

The following properties are implemented:

Name Input Output
CATEGORIES Array<String> Array items separated by ,
CREATED Date Formatted date to spec
DTEND Date Formatted date to spec
DTSTAMP Date Formatted date to spec
DTSTART Date Formatted date to spec
DUE Date Formatted date to spec
EXDATE Array<Date> Array items separated by , formatted to spec
GEO Array<Float> Array items separated by ; (should be [x, y])
LAST-MODIFIED Date Formatted date to spec
RDATE Date Formatted date to spec
TRANSP Boolean TRANSPARENT if true, OPAQUE if false
UID String or none If no input is provided, generates a random GUID
VERSION Number Float with 1 decimal to spec

All other properties (e.g. SUMMARY, LOCATION) are stored as-is without transformations.

Nest a component

const event = new ICS.VEVENT();
event.addProp('DTSTAMP', new Date('2015-07-18 10:00:00'), { VALUE: 'DATE-TIME' });
event.addProp('ATTENDEE', null, {
  CN: 'Sample Company',
  RSVP: 'FALSE:mailto:[email protected]'


Each component contains a list of valid nested components. Only valid components can be nested according to the RFC 5545 spec.

Generate ICS data

cal.toString(); // Returns a string
cal.toBlob(); // Returns a Blob (or throws IncompatiblePlatform if Blob is undefined)
cal.toBase64(); // Returns a base64 encoded string