OneCalendar
OneCalendar: A free multi-provider calendar app with broad device coverage and optional Premium features. Ranked #69 of 193 in Calendar Apps by our editors (3.0/10); pricing: Free plan; best for multi-provider calendar users across devices.
At a glance
- Editor score3.0 / 10
- PricingFree plan
- Best forMulti-provider calendar users across devices
- Free planYes
- Facts checked21 Sep 2026
Where it wins
- Supports Google Calendar, Outlook, iCloud, CalDAV and more
- Offers day, week, month, year and agenda views
- Works offline across Windows, macOS, iOS and Android
Where it doesn't
- Immediate synchronization is a Premium feature
- Premium licensing is separated by platform group
- Custom themes, search and widgets require Premium
Our verdict on OneCalendar
OneCalendar combines calendars from Google Calendar, Outlook, Office 365, Exchange, iCloud, CalDAV and other providers in one application. It is designed for people who manage calendars across services and devices, with support for Windows, macOS, iOS and Android. Core tools include appointment creation, editing and deletion, recurring appointments, meeting invitations, multiple calendar views, offline access and appointment sharing through other apps.
Its main strength is breadth across providers and platforms. The published integrations include Google Calendar, Outlook, Office 365, Exchange, iCloud, Yahoo, GMX, Synology, Nextcloud, ownCloud, Mailbox.org and CalDAV. Users can switch between day, week, month, year and list or agenda views, while calendar colors, appointment colors, widgets, Windows live tiles, dark mode and customizable themes support different workflows. Offline viewing and appointment management also make the app suitable for calendar access when connectivity is limited.
The Basic plan is free and includes calendar viewing and management, multiple calendar providers, multiple views and appointment sharing. Premium adds appointment colors, custom theming, appointment search, up to three years of appointment history, configurable widgets and immediate synchronization. Premium uses a one-time license fee, with licensing separated by platform group. OneCalendar fits users who want a broad, cross-device calendar hub with a capable free starting point. Users who need immediate synchronization, search, widgets or expanded history should plan for Premium, while those seeking a single license spanning every platform group may prefer a differently structured calendar product.
Questions about OneCalendar
Does OneCalendar have a free plan? Yes: the Basic plan is free.
What does OneCalendar run on? Windows, macOS, iOS and Android. It runs as a desktop app and as a mobile app.
What does OneCalendar integrate with? 12 integrations, including Google Calendar, Outlook, Office 365, Exchange and iCloud.
Who is OneCalendar built for? Solo users and small businesses (our editorial estimate).
Your product? Our editors can test OneCalendar in depth and publish a review, labelled as paid · from $149/mo →
OneCalendar pricing
All 2 OneCalendar plans and prices →
OneCalendar fact sheet
| Free plan | Yes |
|---|---|
| Paid from | Not verified |
| Shared calendars | Not verified |
| Time blocking | Not verified |
| Scheduling links | Not verified |
| Calendar sync | Not verified |
| Mobile apps | Ios and android |
| Video meeting support | Not verified |
| Deployment | Desktop, Mobile |
| Platforms | Windows, macOS, iOS, Android |
| Support | |
| Built for | Solo, Small business (editorial estimate) |
| Integrations | 12 integrations: Google Calendar, Outlook, Office 365, Exchange, iCloud, CalDAV … |
| Pricing | Free plan (source) |
| Website | onecalendar.nl |
| Facts checked | 21 Sep 2026 |
OneCalendar integrations
OneCalendar lists 12 integrations on its own site.
- Google Calendar
- Outlook
- Office 365
- Exchange
- iCloud
- CalDAV
- Yahoo
- GMX
- Synology
- Nextcloud
- ownCloud
- Mailbox.org
Alternatives to OneCalendar
- Google CalendarA versatile calendar for personal schedules and Google Workspace collaboration.9.4
- Microsoft OutlookA flexible calendar choice for people and teams already working in Microsoft’s ecosystem.9.2
- Zoho CalendarA low-cost calendar with booking, sync, room reservations, and broad integrations.9.1
See all OneCalendar alternatives →
Used OneCalendar? Be the first to review it
The editor score above is our own research. What this page doesn't have yet is a reader's view — what you used OneCalendar for, what worked and what didn't. No stars are seeded and no review is paid for; an editor reads every one before it appears.
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Reviewed by iTechGuides Editors · Editorial team · Updated Nov 2026
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