Best Open Source Calendar Software 2026

Calendar Software

Calendar Windows Creative Commons Attribution ShareAlike License V3.0 Linux Clear Filters

Browse free open source Calendar software and projects for Windows and Linux 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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1

Cloveriver

Equipment Scheduler

Cloveriver is a side project of Clover, a Simple Lab Information Management System (LIMS). It is used to manage and schedule lab instruments/equipment/rooms. For Clover, please visit https://sourceforge.net/projects/cloversystem/ . Cloveriver is very easy to use. Please visit https://sourceforge.net/p/cloveriver/wiki/Home/ for instructions. I wrote this project in a hurry. The codes are not pretty but are fully functional. This has been tested for over 1 year. Please do NOT store passwords using your browser. This does not work for Cloveriver, because it encodes your passwords before send to the server for verification. Please rate, like, share, and tweet, if you like this program!

Downloads: 0 This Week

Last Update: 2015-11-15
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2

Ice Coral - TimeSpan

Scheduled task and device event evidence

This is a part of the Ice Coral project. The TimeSpan is focused on event evidence, for example scheduled tasks (Windows Task Scheduler, crond). For more info visit Ice Coral - TimeSpan Web Site.

Downloads: 0 This Week

Last Update: 2012-07-13
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3

Site Calendar

Basic calendar to put on a group's website

Creates a basic calendar on the user's website for tracking events. Integrates with phpBB by default for user authentication and roles.

Downloads: 0 This Week

Last Update: 2013-05-30
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4

php calendar

free php calendar

php mysql calendar. appropriate for internal use (for example company), easy to use and install. W3C validated for HTML5 and CSS3. day, month view. filter events by resources, upload files... designed for standalone usage.

Downloads: 0 This Week

Last Update: 2015-06-28
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