Open Source Windows Calendar Software
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Calendar Software for Windows
View 34 business solutionsBrowse free open source Calendar software and projects for Windows below. Use the toggles on the left to filter open source Calendar software by OS, license, language, programming language, and project status.
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Ship Agents FasterGemini Enterprise Agent Platform lets you rapidly build, scale, govern and optimize production-ready agents grounded in your organization's data. The platform enables developers to build custom or pre-built agents for virtually any use case. New customers get $300 in free credits.
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Your monitoring isn't a stack. It's a pile. Fix that.Replace Datadog, New Relic, and Sentry without adding three more dashboards.
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Vtiger CRM
An enterprise-class CRM and more!
Vtiger CRM enables sales, support, and marketing teams to organize and collaborate to measurably improve customer experiences and business outcomes. Vtiger CRM also includes email, inventory, project management, and other tools, providing a complete the business management suite. Download Vtiger CRM here or sign up for a free 15-day free trial of the cloud-based application with free updates and support at https://www.vtiger.com/ -
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Ever wanted to get rid of Outlook ? DavMail is a POP/IMAP/SMTP/Caldav/Carddav/LDAP gateway allowing users to use any mail client with Exchange and Office 365, even from the internet through Outlook Web Access on any platform, tested on MacOSX, Linux and Windows
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Outlook CalDav Synchronizer
Sync Outlook with Google, SOGo or any other CalDAV / CardDAV server
Free Outlook Plugin, which synchronizes events, tasks and contacts between Outlook and Google, SOGo, NextCloud, Horde or any other CalDAV or CardDAV server. Supported Outlook versions are 2021, 2019, 2016, 2013, 2010 and 2007 and Office 365 for Desktop. This project was initially developed as a master thesis project at the University of Applied Sciences Technikum Wien, Software Engineering Degree program. Outlook CalDav Synchronizer is Free and Open-Source Software (FOSS), still you can support the project by donating on Sourceforge or directly within the About dialog of our Plugin. Contact us for enterprise support at https://caldavsynchronizer.org/enterprise/contact -
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RedNotebook is a graphical diary and journal helping you to keep track of notes and thoughts. It includes a calendar navigation, customizable templates for each day, export functionality and word clouds. You can also format, tag and search your entries. Please find the latest releases at https://rednotebook.app
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Our Free Plans just got better! | Auth0You asked, we delivered! Auth0 is excited to expand our Free and Paid plans to include more options so you can focus on building, deploying, and scaling applications without having to worry about your security. Auth0 now, thank yourself later.
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FullCalendar
Full-sized drag & drop event calendar
FullCalendar generates real React virtual DOM nodes so you can leverage Fiber, React's highly optimized rendering engine. With over 300 settings, and more being added every release, FullCalendar can do just about anything. Reduce your project's bundle size by using FullCalendar's modular plugins. With over 10 years of open source and over 100 contributors, FullCalendar will always have a free and open source core. Level-up by purchasing premium plugins and support. FullCalendar seamlessly integrates with the React JavaScript framework. It provides a component that exactly matches the functionality of FullCalendar’s standard API. This is more than a mere “connector”. It tells the core FullCalendar package to begin rendering with React virtual DOM nodes as opposed to the Preact nodes it normally uses, transforming FullCalendar into a “real” React component. You can learn a bit more from this blog post (more info to come). -
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Group Office groupware and CRM
Take your office and CRM into the cloud!
Installation instructions can be found here: https://groupoffice.readthedocs.io/en/latest/install/install.html Group Office is an open source groupware application. It makes your daily office tasks easier. Share projects, calendars, files and e-mail online. It is a complete solution for all your online office needs. From a customer phone call to a project and finally an invoice. The support system helps to keep your customers happy. Group Office is fast, secure and has privacy by design. You can stay in full control of your data by self hosting your cloud and e-mail. Our document editing solution keeps all data on the secured server instead of synchronising it to all user devices. GroupOffice is open source and modular. Which means it’s easy to customise and extend. You can turn off and on features and it enables any developer to create new modules for the platform. -
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Outlook Google Calendar Sync
Sync your Outlook and Google calendars
Offers calendar synchronization between Outlook and Google, including attendees and reminders. Completely free, no install necessary, works behind web proxies and actively developed. Supports all versions of Outlook from 2003 to 2019/Microsoft365 64-bit! Installable and portable options - even runs from a USB thumbdrive. Synchronises items in any calendar folder, including those shared with you. Differential comparison updates only attributes that have changed. Customizable date range to synchronize, past and future. Frequency of automatic syncs, including push-sync from Outlook. Configurable proxy settings, or use Internet Explorer's. Merge new events into existing on the destination calendar. Prompt on deletion of items. Ability to obfuscate custom words for privacy/security. Option to force items as public or private in target calendar. Syncs recurring items properly as a series. -
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Project has moved to github: https://github.com/craigk5n/webcalendar WebCalendar is a PHP application used to maintain a calendar for a single user or an intranet group of users. It can also be configured as an event calendar.
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Zentyal, Linux Small Business Server
Zentyal is a Linux Small Business Server
Zentyal Server is an easy to use and affordable Linux server, specially designed to meet the needs of small and medium businesses Thanks to Zentyal's Samba integration, Zentyal provides native compatibility with Microsoft Active Directory, allowing you to join Microsoft clients to a domain and manage them easily. Zentyal Server incorporates all the network services required in a small and medium business environment: * Directory & Domain Server with native compatibility with Microsoft Active Directory * Mail Server with ActiveSync and webmail * Gateway with firewall and proxy * Infrastructure Server with DNS/DHCP server, Certification Authority and Virtual Private Networks For more information and download, please access the project's home page. -
MyQ Print Management SoftwareBoost your digital or traditional workplace with MyQ’s secure print and scan solutions that respect your time and help you focus on what you do best.
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JDavide (per gli amici JD) è un software gratuito per la gestione dello Studio Legale che aiuta l’avvocato nell’espletamento delle operazioni quotidiane. Funzionalità: pratiche, agenda, formulario, atti, parcellazione, rivalutazione, ecc.
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BRIM is a MVC framework, written in PHP and based on items with a hierarchical relationship. The list of plugins make BRIM a Information Manager with plugins like bookmarks, a calendar, contacts tasks, notes, RSS etc. The application is multilingual.
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Tempus Dominus
A date/time picker widget
Tempus Dominus is the successor to the very popular "eonasdan/bootstrap-datetimepicker". The plugin provide a robust date and time picker designed to integrate into your project. The picker uses the format option to decide what components to show. Set format to LT, LTS or another valid MomentJs format string to display certain components. The picker uses MomentJs to determine the language string. You can use moment-with-locales or you can include whatever local file you need. Start of the week is based on the locale provided. This is defined by moment's locales. If you want to change it, create your own locale file or override. Looking for a template with the datepicker ready to go? Then get check out the templates provided in our website. Bootstrap.js is needed (transition and collapse are required if you're not using the full Bootstrap). -
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time management made easy - timeEdition is targeted at all users in a computer workplace who value detailed documentation of their working hours, whether they use it for customer billing or for monitoring the duration of individual projects.
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qOrganizer is a general organizer that includes a calendar with schedule,reminders,journal/notes for every day, to-do list.But provides features useful for students such as:timetable and a booklet for marks and absences.It's designed to be easy to use.
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FMA is a SMS Manager, Mobile Phone Monitor, Remote Control Agent, Phonebook Manager, Organizer, Fun and much more; whatever you want it to be, it is whatever a mobile phone should have :-) (Currently based on Sony Ericsson features set).
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Lifeograph
Cross-platform, parametric note-taking application
Lifeograph combines powerful features with a clean and thoughtfully designed interface. Your data stays on your device, and built-in encryption keeps privacy at the core. With WYSIWYG editing, your entries always appear in their final form. Integrated data extraction tools transform your journal entries into dynamic tables and charts. -
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BORG is a calendar and task tracking system written in Java. The calendar provides a nice month view, month-print, email reminders, popup reminders and to do list. The task tracker tracks issues through various states.
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Kimai - Time Tracking Software
Time-Tracking for companies and teams with up to 250+ users
Kimai is web based software that tracks work time, and classifies it. It tracks time and prints out a summary of your activities on demand. Yearly, monthly, daily, by customer, by project, by action. FETCH THE LATEST DOWNLOAD FROM GITHUB: https://github.com/kimai/kimai/releases Record expenses and print customizable invoices in different formats. For further information visit: - https://www.kimai.org - https://www.kimai.cloud - https://github.com/kimai/kimai -
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Defalto
Fast, modular open source CRM for growing businesses
Defalto CRM, developed by IT-Solutions4You, is a modern and modular open source CRM system built on over 15 years of real business and CRM development experience. Designed for companies of all sizes, it helps teams manage sales, projects, and customer relationships efficiently through a clean, intuitive interface. The platform combines professional know-how with modern design and functionality. Its free core modules cover essential CRM features, while optional add-ons expand capabilities for advanced business needs. Defalto CRM supports both on-premise and cloud deployment, offering full flexibility and data control. For more info about Defalto CRM visit our page at: https://defalto.com/ Source code available at: https://github.com/IT-Solutions4You/defalto -
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Periodic Calendar
Women menstrual cycles tracking and fertility periods prediction
Periodic Calendar is a GUI application which assists in women menstrual cycles tracking and fertility periods prediction. Periodic Calendar provides support for BBT and sympto-thermal methods which have the highest reliability. -
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Cal.diy
Scheduling infrastructure for absolutely everyone
The Cal.diy project is a fully open-source, self-hosted scheduling platform that provides an alternative to proprietary booking tools while giving users complete control over their infrastructure. It is a community-driven fork of Cal.com that removes all enterprise and commercial features, ensuring that the entire codebase remains MIT-licensed and accessible. The platform enables users to manage bookings, availability, and integrations without relying on external services or subscription models. Built with modern web technologies such as Next.js, React, and PostgreSQL, it offers a robust foundation for building custom scheduling workflows. The system is designed for developers and advanced users who prefer to host and secure their own data rather than depend on third-party providers. It also supports integration with external tools through APIs and authentication systems, allowing flexible customization. -
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WeekToDo
WeekToDo is a Free and Open Source Minimalist Weekly Planner
WeekToDo is a free minimalist weekly planner app focused on privacy. Schedule your tasks and projects with to-do lists and a calendar. Available for Windows, Mac, Linux or online. WeekToDo is a free and Open Source minimalist weekly planner. With WeekToDo you can start improving your productivity by defining and managing your week and your tasks in an easy and intuitive way. WeekToDo mixes the concept of a calendar and tasks list in a single interface. You can set alarms, colors, recurrent tasks, subtasks, and all this in an intuitive and easy way. Also, we care about your privacy so all your data is stored in your device. WeekToDo is a free and Open Source project available for everyone. You can enjoy it like a native app on Windows, macOS, and Linux or directly from your web browser. It is also available in multiple languages. -
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morilog/jalali
This Package helps developers to easily work with Jalali
Jalali calendar is a solar calendar that was used in Persia, variants of which today are still in use in Iran as well as Afghanistan. Read more on Wikipedia or see Calendar Converter. Calendar conversion is based on the algorithm provided by Kazimierz M. Borkowski and has a very good performance. CalendarUtils class was ported from jalaali/jalaali-js. -
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Date Picker Calendar LibreOffice Calc
Date Picker Calendar extension for LibreOffice Calc
Date Picker Calendar (Latest version 2.60) Set a date in selected cell/cells. Creates a calendar push button in the selected cell and places the date in the cell next to the button. All functions are also in the menu: Tools - Add-Ons. It is possible to change certain settings via the 'Settings' button on the help screen. Calendar Help is located in the help menu of LibreOffice. Toolbar buttons: - Date: the date from the calendar will be inserted in the selected cell/cells. - Date <-Button: a calendar button is created in the selected cell, the date is inserted in the cell to the left of the button. - Button-> Date: a calendar button is created in the selected cell, the date is inserted in the cell to the right of the button. -
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Date Picker Calendar OpenOffice Calc
Date Picker Calendar extension for OpenOffice Calc
Date Picker Calendar (Latest version 2.60) Set a date in selected cell/cells. Creates a calendar push button in the selected cell and places the date in the cell next to the button. All functions are also in the menu: Tools - Add-Ons. It is possible to change certain settings via the 'Settings' button on the help screen. Calendar Help is located in the help menu of OpenOffice. Toolbar buttons: - Date: the date from the calendar will be inserted in the selected cell/cells. - Date <-Button: a calendar button is created in the selected cell, the date is inserted in the cell to the left of the button. - Button-> Date: a calendar button is created in the selected cell, the date is inserted in the cell to the right of the button.
