Alternatives

Products that do what SpotOn.it - Synchronous Calendar Subscriptions does

1. 1CM
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2. 2CA
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3. 3CP
   CalendarPipe – programmable calendar sync via OAuth or email invites▲5

   Jun 2026 · calendarpipe.com

4. 4RA
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   2020 · reclaim.ai

5. 5
   CalendarPipe▲155

   Programmable calendar sync for humans and AI agents

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6. 6NS
   Nettu Scheduler – A self-hosted calendar and scheduler server▲129

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7. 7
   Clipse▲124

   Synchronized calendar availability across timezones

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8. 8BC
   Boomerang Calendar - a smart calendar assistant in your Gmail▲86

   2012 · boomerangcalendar.com

9. 9
   ShadowCal▲95

   Sync your Outlook Calendar to Google Calendar

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10. 10SA
    Sync any Google Calendar you can access to your own MySQL database▲24

    2019 · app.getaika.com

11. 11
    SyncThemCalendars▲83

    Setup a synchronization between calendars

    2019

12. 12NA
    New API – Stripe for calendars▲5

    2014 · onediary.com

13. 13FA
    Futurenda – AI Task Scheduler, Now with Google Calendar Sync▲13

    2017 · futurenda.com

14. 14ES
    Easily Schedule with Busy People – Real-Time Calendar Sharing▲11

    2015 · web.meekan.com

15. 15AR
    A React.js yearly calendar component▲94

    2015 · github.com

16. 16AA
    Aeon – a lightweight date picker built with web components▲34

    2020 · github.com

17. 17
    Canary▲57

    Sleek calendar app that makes scheduling a breeze

    2013

18. 18AC
    A Chrome desktop app for Google Calendar with a nice interface▲10

    2016 · chrome.google.com

19. 19BA
    Building an E-Ink Calendar and a UI Toolkit along the way▲64

    2020 · rahulrav.com

20. 20MC
    Modern Calendar Embed for Google Calendar▲12

    2020 · gra0007.github.io

21. 21DR
    Desktop reminder app for Google Calendar with push support▲7

    2014 · chrome.google.com

22. 22CS
    Cronhooks – Schedule one time or recurring webhooks▲31

    2019 · cronhooks.io

23. 23MS
    Meekan, Slack scheduling robot: matches availability, syncs calendars▲16

    2015 · meekan.com

24. 24TT
    Time tracker for freelancer with shareable URLs▲14

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