OneCalendar review
A free multi-provider calendar app with broad device coverage and optional Premium features.
Reviewed by iTechGuides Editors · Editorial team · Updated Nov 2026
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).
OneCalendar pros and cons
- 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
OneCalendar fact sheet, pricing and score →
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