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Best Atlas Calendar Alternatives in 2026

Updated

20 platforms from calendar apps ranked against Atlas Calendar on the same published basis.

  1. 1
    Lark Free plan AndroidapiiOSLinuxMac 8.8
    Atlas Calendar vs Lark
  2. 2
    Calendar.com Free plan AndroidapiextensioniOSWeb $20/mo8.8
    Atlas Calendar vs Calendar.com
  3. 3
    Teamup Free plan AndroidapiiOSWeb $12/mo8.7
    Atlas Calendar vs Teamup
  4. 4
    7shifts Free plan AndroidapiiOSWeb Free8.1
    Atlas Calendar vs 7shifts
  5. 5
    Slotly Free plan AndroidapiWeb $0.83/mo7.9
    Atlas Calendar vs Slotly
  6. 6
    Mozilla Thunderbird Free plan Open sourceAndroidLinuxMacWin Free7.6
    Atlas Calendar vs Mozilla Thunderbird
  7. 7
    Microsoft Outlook Calendar Free plan AndroidiOSMacWeb $1.67/mo7.5
    Atlas Calendar vs Microsoft Outlook Calendar
  8. 8
    Proton Calendar Free plan AndroidiOS Free7.4
    Atlas Calendar vs Proton Calendar
  9. 9
    Reclaim AI Free plan extensionWeb $10/mo7.4
    Atlas Calendar vs Reclaim AI
  10. 10
    EGroupware Free trial Open sourceWebLinuxWinMac €21.90/mo7.4
    Atlas Calendar vs EGroupware
  11. 11
    Rallly Free plan apiself-hostedWeb $0.50/mo7.4
    Atlas Calendar vs Rallly
  12. 12
    Notion Calendar Free plan AndroidiOS Free7.3
    Atlas Calendar vs Notion Calendar
  13. 13
    Doodle Free plan Web $11/mo7.3
    Atlas Calendar vs Doodle
  14. 14
    Cozi Free plan AndroidiOSWeb $3.25/mo7.3
    Atlas Calendar vs Cozi
  15. 15
    TimeTree Free plan AndroidiOSWeb $3.75/mo7.3
    Atlas Calendar vs TimeTree
  16. 16
    Google Calendar AndroidiOS $7/mo7.2
    Atlas Calendar vs Google Calendar
  17. 17
    Tuta Calendar Free plan AndroidiOS €3/mo7.2
    Atlas Calendar vs Tuta Calendar
  18. 18
    Fantastical Free plan iOSMacWin Free7.2
    Atlas Calendar vs Fantastical
  19. 19
    FlowSavvy Free plan AndroidiOSWeb 7.2
    Atlas Calendar vs FlowSavvy
  20. 20
    Trevor AI Free plan Web $0.42/mo7.2
    Atlas Calendar vs Trevor AI

Atlas Calendar alternatives compared

#PlatformScoreFree planFromRuns on
1Lark8.8Free plan—Android, API, iOS, Linux, Mac, Web, Windows
2Calendar.com8.8Free plan$20/moAndroid, API, Browser, iOS, Web
3Teamup8.7Free plan$12/moAndroid, API, iOS, Web
47shifts8.1Free planFreeAndroid, API, iOS, Web
5Slotly7.9Free plan$0.83/moAndroid, API, Web
6Mozilla Thunderbird7.6Free planFreeAndroid, Linux, Mac, Windows
7Microsoft Outlook Calendar7.5Free plan$1.67/moAndroid, iOS, Mac, Web
8Proton Calendar7.4Free planFreeAndroid, iOS
9Reclaim AI7.4Free plan$10/moBrowser, Web
10EGroupware7.4No€21.90/moWeb, Linux, Windows, Mac
11Rallly7.4Free plan$0.50/moAPI, self-hosted, Web
12Notion Calendar7.3Free planFreeAndroid, iOS
13Doodle7.3Free plan$11/moWeb
14Cozi7.3Free plan$3.25/moAndroid, iOS, Web
15TimeTree7.3Free plan$3.75/moAndroid, iOS, Web
16Google Calendar7.2No$7/moAndroid, iOS
17Tuta Calendar7.2Free plan€3/moAndroid, iOS
18Fantastical7.2Free planFreeiOS, Mac, Windows
19FlowSavvy7.2Free plan—Android, iOS, Web
20Trevor AI7.2Free plan$0.42/moWeb
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Questions about Atlas Calendar alternatives

What is the best alternative to Atlas Calendar?

Lark, number 1 in calendar apps with a score of 8.8 out of 10. The others here: Calendar.com, Teamup, 7shifts and 16 more.

What is the best free alternative to Atlas Calendar?

Lark is the best-ranked alternative with a free plan. 18 of the 20 alternatives here publish a free plan on their own pricing pages.

Is there an open-source alternative to Atlas Calendar?

Yes: Mozilla Thunderbird, EGroupware.

How are these alternatives ranked?

Ranked on what each maker publishes, open and connectable first: a public API, open-source code, the depth of its documentation and a free tier to try it on. Model lists are sorted by the figure in their title, exactly as each provider publishes it.