Free Portable Download Calendar Software For Pc May 2026

Launched as a standalone app, Notion Calendar has quickly become a favorite for power users who want a "command center" feel.

It unifies all your external calendars into one clean interface with customizable themes and desktop widgets. Download: Available as a free app in the Microsoft Store. 4. Mozilla Thunderbird (Open Source) free download calendar software for pc

if you use Notion for project management or prefer a modern, minimal UI. Launched as a standalone app, Notion Calendar has

if you already use Microsoft Office or need to manage multiple email accounts. Launched as a standalone app

Since it’s open-source, your data remains on your local machine unless you choose to sync it. It includes the "Lightning" calendar component by default.

It is completely free for personal use and includes event lists, task management, and alarms.