Offers calendar synchronisation between Outlook and Google, including attendees and reminders. Completely free, no install necessary, works behind web proxies and actively developed.




Keeper is described as 'Open-source calendar syncing tool that can be used to sync the blocks of time marked as "busy" on your personal, work, business and school calendars' and is a Calendar app in the office & productivity category. There are more than 10 alternatives to Keeper, not only websites but also apps for Windows, SaaS, Mac and Microsoft Outlook. The best Keeper alternative is Outlook Google Calendar Sync, which is both free and Open Source. Other great sites and apps similar to Keeper are OneCal, SyncThemCalendars, gSyncit and Outlook CalDav Synchronizer.
Offers calendar synchronisation between Outlook and Google, including attendees and reminders. Completely free, no install necessary, works behind web proxies and actively developed.




OneCal is a productivity tool that aims to make calendar synchronization as easy as possible. It has a very intuitive UI, supports multi-way syncs, and is fully configurable (you can choose to sync event titles, descriptions, and participants, assign colors to clone events...




SyncThemCalendars allows you to block time in one calendar based on events in another calendar.
gSyncit™ is a Microsoft Outlook add-in that allows for the synchronization of Outlook calendars, contacts, notes, and tasks with your Google account.




Free Outlook Plugin, which synchronizes events, tasks and contacts between Outlook and Google, SOGo, Horde or any other CalDAV or CardDAV server. Supported Outlook versions are 2016, 2013, 2010 and 2007.



This utility synchronizes Outlook calendar and task list entries to a Google calendar, vice versa, and both ways. Create profiles to sync multiple calendars. Modify sync frequency, direction, and filters. Outlook 2007 to 2016 are supported.


Spanning Sync 3 is the one app that syncs both iCal with Google Calendar and Address Book with Google Contacts. It gives you even better control over how your information syncs, and is now up to 10x faster!




SYNCING.NET offers powerful Data and Outlook synchronization for individuals, professionals and businesses. By providing secure PC synchronization, integrated file and Outlook sharing, users can access all their data at any time and any place.