Atlas Calendar
What Atlas Calendar is
Atlas Calendar is a free web calendar for shared team scheduling, recurring events, tasks, and CRM-linked events. The maker, founded in 2011 and headquartered in Tempe, AZ, describes the Atlas platform as serving professional services businesses typically using 1 to 500 users. Two-way synchronization connects Google, Outlook, and iCloud, while a native CalDAV server supports Apple Calendar, Thunderbird, and standard CalDAV clients. Recurring events can follow daily, weekly, monthly, yearly, or custom RRULE schedules, and attendees can accept, decline, or respond tentatively. Users can create task lists with due dates and priorities, attach AtlasFS files to events, and import events from ICS, Google Calendar, or Outlook. The Free plan costs nothing and includes two-way sync, CalDAV, shared team calendars, recurring events and tasks, and CRM-linked events. Atlas says transit data uses TLS and connected-account tokens use AES-256-GCM at rest.
Who it suits
Atlas Calendar suits teams wanting shared browser calendars, synchronized accounts, recurring work, and CRM-linked events. It is especially relevant to professional services organizations within the stated user range.
What it does well
- Free plan
- Two-way Google, Outlook, and iCloud sync
- Native CalDAV server
- Shared team calendars and recurring tasks
- CRM-linked events
What to know first
- Web platform only
- Organization data is deleted after 90 days
- Designed for professional services businesses
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Free | For every user · Two-way sync with Google, Outlook & iCloud · Native CalDAV support · Shared team calendars · Recurring events & tasks · CRM-linked events | Free |
As hyperionworks.com lists them, read 12 Oct 2026. The maker's own page has the final word.
Verdict
Atlas Calendar provides a broad set of shared scheduling and synchronization functions at no listed cost. Review its web-only access and stated data-retention period when assessing it for organizational use.
Facts from Atlas Calendar's own pages
- Availability and audience
- Atlas Calendar is described as in production and available now; the Atlas platform is designed for professional services businesses, typically with 1 to 500 users. · hyperionworks.com, 12 Oct 2026
- CalDAV
- It provides a native CalDAV server for Apple Calendar, Thunderbird, and standard CalDAV clients. · hyperionworks.com, 12 Oct 2026
- Calendar sync
- It offers two-way sync with Google Calendar, Outlook Calendar, and Apple iCloud. · hyperionworks.com, 12 Oct 2026
- Connected account data
- Atlas says it does not use connected-account data for advertising or machine-learning training, and does not access connected accounts in the background except for explicitly enabled calendar sync. · hyperionworks.com, 12 Oct 2026
- Data retention
- After an organization unsubscribes from an app, its data in that app is retained for 90 days before permanent deletion. · hyperionworks.com, 12 Oct 2026
- Events and attendees
- Recurring events support daily, weekly, monthly, yearly, and custom RRULE schedules; attendees can accept, decline, or respond tentatively. · hyperionworks.com, 12 Oct 2026
- Founded
- 2011 · hyperionworks.com, 28 Sept 2026
- Free plan
- Yes · hyperionworks.com, 22 Sept 2026
- Headquarters
- Tempe, AZ · hyperionworks.com, 28 Sept 2026
- Import
- Users can import existing events from an ICS file, Google Calendar, or Outlook. · hyperionworks.com, 12 Oct 2026
- Purpose
- Atlas Calendar is a shared team calendar for creating events, managing recurring schedules, sharing calendars across an organization, and linking events to CRM contacts. · hyperionworks.com, 12 Oct 2026
- Security
- Atlas says data in transit is encrypted with TLS and connected-account tokens are encrypted at rest with AES-256-GCM. · hyperionworks.com, 12 Oct 2026
- Shared calendars
- Teams can create calendars for teams, projects, or rooms and set per-user read or write permissions. · hyperionworks.com, 12 Oct 2026
- Support
- The maker lists [email protected] as its support contact. · hyperionworks.com, 12 Oct 2026
- Tasks and attachments
- Users can create task lists with due dates and priorities, and attach AtlasFS files to events for attendees with access. · hyperionworks.com, 12 Oct 2026
Where Atlas Calendar stands on Freedom251
- Calendar apps#102 of 194