Calendar GitHub Repositories (2026) · Open Source Tools

Ultimate calendar for your React app.

Menu bar calendar for macOS - MVVM | RxSwift | AppKit | SwiftUI

Full-sized drag & drop JavaScript event calendar with resource & timeline views

A simple calendar with events, customizable widgets and no ads.

Open World Holidays Framework

A perpetual Jewish Calendar

Query and format a set of opening hours

Complex period comparisons

📅 A sleek and highly customizable calendar card for Home Assistant, designed for performance and a clean, modern look.

Generate add to calendar links for Google, iCal and other calendar systems

A modern, open-source Full Calendar alternative for React. Month, week, day, and year views with drag-and-drop, horizontal and vertical resource views, and RFC 5545 recurring events — all MIT licensed.

A CalDAV web client similar to Google Calendar

Official public Markdeep source archive

An Easy to Use Calendar for iOS (Swift 5.0)

a calendar server aiming to be simple, fast and passwordless

Invite others to grab times on your calendar. Choose a date. Make appointments as easy as it gets.

PHP Date Recursion library

Vue.js Functional Calendar | Component/Package

Groupware for citizens to organize on the Web

Free, open-source church management software for people, families, groups, events, attendance, giving, volunteers, and more. No subscription. Your data is yours.