Productivity, meeting scheduling, task management - they all have one thing in common: a calendar. No matter how many strategies we try, a well-organized calendar remains the foundation of keeping our time and tasks in order. That's why we've put together this comprehensive guide to the best online calendar apps of 2025.
We'll explore our top picks for different categories, from free personal calendar apps to more advanced business calendar tools. Because maybe you want a simple and efficient calendar like Google's; or, perhaps, you need to schedule meetings with your clients, in which case you want Zeeg. But hopefully our view on this will help you find the perfect digital calendar to match your needs.
What are the best calendar apps in 2025?
- Best calendar for external appointment booking: Zeeg
- Best free calendar app overall: Google Calendar
- Best calendar for Microsoft/Windows users: Microsoft Outlook Calendar
- Best calendar for Apple Users: Apple Calendar
- Best calendar for Linux users: Lightning Calendar
- Best AI calendar: Motion
- Best calendar for productivity: Any.do
- Best for simple calendar app: Moleskine Studio
Best calendar apps: Overview
Best calendar apps: In-depth analysis
1. Zeeg: Best calendar for external appointment booking
Zeeg stands out as a complete calendar scheduling app for external appointment booking, offering a comprehensive solution for businesses and professionals who need to schedule meetings with clients or partners. This all-in-one calendar app combines powerful scheduling features with a user-friendly interface, making it an excellent calendar for business needs. Zeeg is a great option for freelancers, consultants, and businesses of all sizes that need to streamline their appointment booking process. It offers a professional experience to their teams and clients, being able to keep schedules as collaborative calendars, that they can control fully. And one can keep using other calendars, like Google’s or Apple’s, and integrate them with Zeeg for more advanced options.
Key features:
- Customizable booking pages
- Individual and group scheduling
- Automated scheduling and reminders
- Time zone detection
- Round Robin to Routing Forms that optimize client booking
- Integration with other calendar apps, video conferencing tools, CRM software
- Fully GDPR compliant and end-to-end encryption
- Payment processing integration
While Zeeg doesn't emphasize AI, it does have smart ways to optimize your scheduling. The app can automatically find both parties’ timezones and suggest the best meeting times based on your availability and preferences, thus reducing the back-and-forth often associated with scheduling.
You’ll get great integration options, connecting easily with popular calendar apps like Google Calendar, Outlook, and Apple Calendar. Zeeg also integrates with various video conferencing tools (Meet, Teams, Zoom), CRM systems (Salesforce, Zapier, Hubspot), and payment platforms, making it a versatile choice for business users.
Pros and cons:
✅ Optimizes external appointment booking, increasing lead generation
✅ Professional and customizable booking pages
✅ Excellent integration options (Zapier, Google Calendar, Outlook, Teams, PayPal)
✅ Round-robin feature to get the right person to customers
✅ Automated workflows that make scheduling efficient
✅ Fully GDPR compliant, end-to-end encryption
✅ Strong focus on security and compliance
✅ Cost-friendly when compared to competition
❌ Free version has just one calendar and two scheduling pages
❌ Still a relatively new tool
❌ No app available yet
Pricing
Zeeg offers a free plan with basic features, and that’s yours to keep. The paid plans start from $7 per user/month. For all paid plans there’s a 14-day trial period, at the end of which you may extend your subscription or cancel it.
- Free: no cost, free forever
- Professional: $7 per user/month
- Business: $12 per user/month
- Enterprise: Customized
The free plan already lets you schedule an unlimited number of meetings, use your own booking page (it’s like an efficient digital card), and send automated event notification and calendar invites. But there’s a few things you might have to pay for: if you want more calendar connections and scheduling pages or have more attendees in your meetings, you should try the first paid plan (Professional). And for advanced options like multiple host meetings, round-robin features, or routing forms, then the Business plan will be better.
2. Google Calendar: Best overall free calendar app
Google Calendar takes the crown as the best free calendar app, offering a powerful mix of simplicity and functionality. This digital calendar, most likely the most popular one, is great for individuals and teams seeking a versatile, user-friendly solution that works well with other Google services. That’s a lot. And not only individuals use it, but smaller and bigger businesses do it too, through Google Workspace. The truth is that Google’s cross-platform support makes this app a go-to choice for many, thus being one of the best free online calendars for many.
Key features:
- Event creation and management
- Shared calendars
- Smart scheduling
- Integration with Google services
- Mobile apps
- Time zone support
- Complete free calendar for simple use cases
In terms of AI functionalities, we can’t really say that Google Calendar has an extensive features package, but it does offer some smart things. It can suggest event titles, locations, and attendees based on your past usage. It also automatically creates events from Gmail, such as flight bookings or restaurant reservations. The "find a time" feature uses AI to suggest optimal meeting times for multiple participants, which is a nice touch for teams.
And when it comes to integrations, Google Calendar does stand out as a calendar sync app. It integrates natively with Google Workspace apps and syncs with many many other calendar services. And it has a super wide range of direct or third-party integrations with popular tools like Trello, Asana, Slack, Zoom, etc. Basically, any company in the game needs to be able to connect to Google tools, otherwise things will get tough for them.
While Google Calendar shines in many areas, it's not without its shortcomings. Some users might find themselves frustrated by the lack of advanced customization options. If you're looking to book rooms or resources, or need appointment slots, you won’t find this in the free version. Not a problem if you can pay, that’s true. But syncing with non-Google calendars can sometimes be hit or miss, with some users reporting some hiccups. For those juggling complex projects or coordinating large teams, that might be annoying. Not that other tools won’t have similar problems, by the way—but it’s still worth mentioning.
Pros and cons:
✅ Free for individual use
✅ Intuitive interface
✅ Great sharing and collaboration features
✅ Mobile app
✅ Seamless integration with Google services
❌ Very limited customization options
❌ Integrations aren’t always great (think of Zoom, Trello or Outlook)
❌ Data security isn’t the greatest: not end-to-end encrypted
❌ Advanced features may require a Google Workspace subscription
Pricing
Google Calendar is free for individual users, while Google Workspace paid plans are priced at three levels, all of them having a 14-day trial:
- Business Starter: $6/user/month
- Business Standard: $12/user/month
- Business Plus: $18/user/month
- Enterprise: customized
The Starter plan includes things like security and management controls, or video meetings for up to 100 people, so it already adds on the free version (let's not forget that Google Meet is one of the best video conferencing tools). But if you want more advanced features like appointment booking pages, then you need the Business Standard Plan. And after that, it’s mostly about increasing the storage per user, number of participants per meeting, and other security and management options.
3. Microsoft Outlook Calendar: Best calendar for Microsoft users
Microsoft Outlook Calendar is a somewhat natural choice for Microsoft users, as it offers great integration options with the Microsoft ecosystem. And users who need advanced scheduling and task management features might like it as a more complete work calendar app too.
Key features:
- Integrated email and calendar
- Meeting scheduling assistant
- Shared calendars
- Categories and color-coding
- Mobile app
- Advanced recurrence options
Outlook Calendar is quite good in terms of AI, using Microsoft's AI capabilities to suggest replies for meeting invitations, and to give travel time suggestions based on your location and traffic conditions. The calendar also integrates with Cortana for voice-controlled management.
And talking about integrations, Outlook Calendar is pretty complete. It integrates nicely with Microsoft 365 apps; and can also sync with other calendar services through the Microsoft AppSource. In any case, if you have some specific calendar tool you’d like to connect to, it’s always good to double check if they integrate with Outlook.
It’s true that Outlook Calendar is a great tool, but it also comes with its own set of challenges. Its feature-rich interface can be a double-edged sword, overwhelming those who prefer an easier experience. Plus, the full suite of features is locked behind a Microsoft 365 subscription, which might strain the budgets of individuals or small businesses. Mobile users often find themselves wishing for a more intuitive app experience compared to the desktop version.
Pros and cons:
✅ Deep integration with Microsoft 365 suite
✅ Powerful email-calendar combination
✅ Advanced scheduling and organization features
✅ Great security and encryption options
❌ Can be overwhelming for users who prefer simplicity
❌ Full feature set requires a Microsoft 365 subscription
❌ Some users find the interface cluttered
Pricing:
Microsoft 365 also has different subscription options, all of them with one free month trial option:
- Business Basic: $6/user per month (billed annually) or $7.20 if you pay annually
- Business Standard: $12.5/user per month (billed annually) or $15 (billed monthly)
- Business Premium: $22/user per month (billed annually) or $26.40 (billed monthly)
- Microsoft 365 Apps for business (only includes apps): $8.25/user per month (billed annually) or $9.90 (billed monthly)
All paid plans include basic things on your calendar, like scheduling meetings, managing your calendar, responding to invitations using shared calendars, sharing available meeting times or using reminders. If you need reporting on data for webinar registration and meeting attendance, then you need to go for the Standard plan. And if you want to have more advanced security or device management options, then the Premium will be for you (likely for bigger companies).
4. Apple Calendar: Best calendar app for Apple users
With no surprise, Apple Calendar (also known as iCal) is the top calendar app for Apple users, especially those looking for the best calendar app for iPads and iPhones. It offers a sleek, intuitive interface that integrates perfectly with the Apple ecosystem. But it’s not just about already being an Apple user (though that could be crucial). Those who want a clean, straightforward calendar interface will appreciate Calendar. It's also great for users who value privacy and data security, as well as those who need basic calendar functionality without overwhelming features.
Key features:
- iCloud sync
- Natural language input
- Time zone support
- Shared calendars
- Integration with Apple Mail
- Siri integration
While not heavily focused on AI, Apple Calendar does offer some nice features. It provides Siri suggestions for event creation based on your emails and messages, travel time estimates based on current location and traffic conditions, and intelligent suggestions for event locations and participants.
Apple Calendar's integrations are limited but useful. It integrates natively with other Apple services and supports CalDAV for syncing with other calendar services, and third-party app integrations are available through iOS and macOS APIs. However, connecting to other apps is sometimes difficult, and some of these might one day drop that option. If you try connect Calendly to Apple, as an example, you'll find that this used to be possible, but not anymore.
Simplicity is Apple Calendar's strength, but it's also its weakness. You won't find the advanced scheduling options or in-depth collaboration tools that some other apps offer (for instance, if you compare Google Calendar vs Apple Calendar, you'll feel that Apple's option feels limited). While it's great for personal use, it falls short when it comes to complex team or business scheduling. Also, its seamless integration with the Apple ecosystem is a blessing for Apple users, but can be a curse if you're working with non-Apple services and devices. And if you're big on customization, well...you might find yourself wanting more.
Pros and cons:
✅ Clean and intuitive interface
✅ Seamless integration with Apple ecosystem
✅ Strong privacy and security features
✅ The app is free
❌ Lack of advanced scheduling features
❌ Limited customization options
❌ Not ideal for non-Apple users
❌ Integrations with iCloud are sometimes unavailable or difficult to implement
Pricing:
Apple Calendar’s pricing is somewhat different from other providers. It’s free to have the calendar on your Mac, iPhone or iPad, and you have access to all of Calendar’s features. But if you want other things and more storage capacity, then you need to pay for an iCloud+ subscription:
- iCloud+ with 50GB: $0.99/month
- iCloud+ with 200GB: $2.99/month
- iCloud+ with 2TB: $9.99
- iCloud+ with 6TB: $29.99
- iCloud+ with 12TB: $59.99
With the paid plans, you basically get more storage, plus some other things like iCloud enhanced privacy, the option to hide your email, or custom email domain. Again, it might be a great solution if you have an iPhone and a Mac. But do look into other options if you’re into starting a business, for example.
👉 Read more: How to Sync Google Calendar with Apple Calendar
5. Lightning Calendar: Best calendar for Linux users
Built as an extension for the Thunderbird email client, Lightning Calendar is mostly for Linux users. This open-source calendar software free solution integrates well with the Thunderbird tools, making it a great choice among privacy-conscious users and those who prefer open-source software. If you're a Linux fan who values customization and data control, you'll find Lightning Calendar particularly appealing. It's especially suited for Thunderbird email client users and organizations looking for a flexible calendar solution that can be tailored to specific needs.
Key features:
- Integration with Thunderbird email client
- Support for multiple calendars
- CalDAV and CardDAV support
- Customizable views
- Task management
- Offline access
Lightning Calendar doesn't offer AI-powered features. Its main strength lies in its open-source nature, allowing users to modify and extend its functionality as needed. And in terms of integrations, this calendar works well with other open-source tools and supports standard protocols like CalDAV and CardDAV, allowing for easy synchronization with various calendar services and devices.
As an open-source option, Lightning Calendar marches to the beat of its own drum. This means you might be waiting longer for new features and updates compared to commercial products. While functional, the user interface might not win any beauty contests. If you're always on the go, the limited mobile support could be a deal-breaker. And here's the kicker: it's tied to the Thunderbird email client. So if you're not a fan of bundled email and calendar apps, you might want to look elsewhere.
Pros and cons:
✅ Open-source and highly customizable
✅ Strong privacy and data control
✅ Seamless integration with Thunderbird
✅ No cost
❌ More difficult to learn for non-technical users
❌ Limited mobile support compared to other options
❌ Fewer advanced features than some proprietary solutions
❌ Requires Thunderbird email client
Pricing
Lightning Calendar is free to use as part of the Thunderbird email client.
6. Motion: Best AI calendar
The title of best AI calendar goes to Motion, a calendar tool that uses machine learning to manage time and tasks. It can be a great addition for professionals and entrepreneurs, or anyone looking to improve their productivity. Especially for those who juggle multiple projects and need help prioritizing tasks, Motion can be a good tool.
Key features:
- AI-powered scheduling
- Automatic task prioritization
- Project management integration
- Smart meeting planning
- Time blocking
- Adaptive daily planning
Motion's AI capabilities are its biggest feature. The app uses machine learning algorithms to understand your work patterns, automatically schedule tasks, and adapt your calendar based on your priorities and deadlines. It can even reschedule less urgent tasks when unexpected high-priority items come up. And in terms of integrations, it works well with some of the most popular productivity and project management software, pulling in tasks from various sources and scheduling them in the calendar (like Zoom, Google Calendar, iCloud, etc).
In the end, we can say Motion's AI-driven approach is cutting edge. But it's not without its quirks. If you like to be in the driver's seat of your schedule, Motion's automated scheduling might feel like backseat driving. You’ll need to adapt to the AI's decision-making process, which could take a while. And let's be real: AI isn't perfect. It can sometimes miss the mark, especially with complex or nuanced scheduling needs. Plus, the price point is higher than your average calendar app, which might be a tough sell for some.
Pros and cons:
✅ AI-driven scheduling and optimization
✅ Seamless integration of tasks and calendar
✅ Adaptive planning that adjusts to changing priorities
✅ Time-saving automation features
❌ Steeper learning curve due to advanced AI features
❌ Higher price point compared to traditional calendars
❌ May feel too automated for users who prefer manual control
❌ Requires consistent use to maximize AI benefits
Pricing:
Motion offers a 7-day free trial, with paid plans starting at $19 per month for individuals and $12 per user per month for teams.
- Individual (one user): $19/month (billed annually) or $34/month (billed monthly)
- Business Standard (up to 20 users): $12/month/user (billed annually) or $20 (billed monthly)
- Business Pro (more than 20 users): customized
The cheapest plan isn’t exactly cheap. In any case, it offers things like automated scheduling and planning with A.I., project and task management, and booking pages and templates. And it’s only for one user. For more users, you’ll have to pay. But that also includes different types of automations, team project management, or time tracking.
7. Any.do: Best calendar for task management
Any.do is a great calendar to organize your to-do lists, offering a mix of task management with the calendar's basic. The app helps users stay organized by integrating lists, reminders, and events in one place, making it a great option for productivity. It's particularly useful for those who want a unified view of their responsibilities and schedule in a personal calendar app.
Key features:
- Integrated task list and calendar
- Smart reminders
- List sharing and collaboration
- Location-based reminders
- Recurring tasks and events
- Cross-platform synchronization
Any.do AI has some AI features like suggested tasks based on your past behavior and intelligent reminders that take into account your location and schedule. As a calendar reminder app, it excels in keeping users on top of their tasks and appointments.
When it comes to integrations, it goes well with other calendar services like Google Calendar, Outlook, and Apple Calendar. It also offers integrations with popular productivity tools and can sync across multiple devices and platforms.
Any.do tries to be a jack-of-all-trades, but this comes with some trade-offs. Your calendar view can quickly turn into a cluttered mess when you've got a lot on your plate. Syncing across multiple calendars? Be prepared for occasional issues. If you're not willing to open your wallet, you might find the free version a bit too bare-bones. And while it does a decent job of merging tasks and calendar events, it might not have the scheduling muscle of dedicated calendar apps.
Pros and cons:
✅ Seamless integration of tasks and calendar
✅ Clean, intuitive interface
✅ Excellent cross-platform support
✅ Useful collaboration features
❌ Some features only available in teams plans
❌ Calendar view can feel cluttered with many tasks
❌ Not many features nor customization options compared to dedicated calendar apps
Pricing:
Any.do offers a free version with basic features, with premium plans starting at $4.99 per month when billed annually. Here’s some more info:
- Personal: free
- Premium: $4.99 (billed annually) or $7.99 (monthly payments)
- Family: $8.33 or $9.99
- Teams: $4.99 or $7.99
Overall their prices seem cheaper than many of the tools we’ve seen before, especially if you pay annually. If a task planner is what you want, then it might pay off. The personal plan comes with the basics, like the calendar, tasks and lists, reminders, a daily planner, and cross-device sync. On top of this, with paid plans you can add more people to the planner, have shared tasks, recurring tasks, Whatsapp reminders and some AI touches.
8. Moleskine Studio (Timepage): Best for simple calendar app
When it comes to simplicity, Timepage, from Moleskine Studio, is amongst the best. It brings the elegance of Moleskine's physical notebooks to the digital realm. The app itself, called Timepage, can be complemented with two other apps: Actions (focused on to-do lists), and Flow (replicated the classic Moleskine notebook on iPads and iPhones); and they all try to provide a clean, visually appealing interface for managing your time. But be aware that this specific feature, the calendar app, only works for iOS.
Key features:
- Minimalist design
- Weather integration
- Natural language input
- Heatmap view of busy days
- Travel time estimates
- Custom event icons
While Moleskine Studio doesn't have a lot of AI features, it does offer smart functionalities like travel time estimates and natural language input for easy event creation.
In terms of integrations, Moleskine Studio in general works well with popular calendar services (Google included) and can sync across multiple devices. However, if you want to use Timepage app, that will be iOS only.
Moleskine Studio is a looker, but beauty is sometimes skin deep. If you're a power user hankering for advanced features like complex recurring events or extensive collaboration tools, you might be left wanting. Third-party integration options are on the slim side compared to some beefier calendar solutions. The minimalist design is easy on the eyes, but it can sometimes make simple tasks feel like a treasure hunt. And if you're not a fan of subscriptions, the fact that you need one for full access might be a deal-breaker.
Pros and cons:
✅ Clean, visually appealing design
✅ Intuitive user interface
✅ Calendar app (Timepage) is just for iOS
✅ Useful features like weather integration, travel time estimates and contacts
✅ Cross-platform synchronization
❌ Limited advanced features compared to other calendar apps
❌ Also fewer integration options
❌ May be too simple for advanced users
Pricing:
Moleskine Studio offers a 7-day free trial, in case you want to give it a shot. After that, you’ll have to pay for their different apps. The Timepage membership costs $2.49 per month, or $14.99 if you pay for the whole year, and the same price applies for the other apps. But if you want all three - Timepage, Actions and Flow - then the Moleskine Studio Bundle membership could be worth it.
Bottom line: So, which calendar app is the best?
That really depends on people's needs. If you're looking for the best appointment schedulers, then Zeeg is a great alternative (or complement) to Google Calendar. You'll have a neat meetings scheduling system, internally and externally. But if you want something simpler, Moleskin's solution or Google Calendar might be right for you. Or Apple Calendar, in case you're already using it on other devices. It really depends.
But there's many other things you can look at when choosing the right online calendar. We've prepared a list of key aspects to help you:
- Do you need a simple calendar to organize your days, or something more complex?
- Is it for personal reasons, business needs, or both?
- Do you have specific scheduling needs or just a 1.1 chat every now and then?
- Do you need integrations with video conferencing tools and/or other tools?
- Do you need any other functionalities like CRM? API? Task management tools?
- Is design relevant to you?
Want to improve your scheduling experience now, avoiding no-shows and increasing your leads? Try Zeeg.
Other frequent questions when choosing the best calendar app
What to consider when choosing a calendar app?
Choosing the right calendar app can really be a game-changer, whether you're working on personal tasks or complex business schedules.
1. Start by thinking about what you really need. Are you looking for a simple app to keep track of daily tasks, or do you need something more robust for intricate scheduling? Consider whether it's for personal use, work, or both. If it's for personal use, do you need to share calendars with family members? For work, think about team collaboration features or client management tools.
2. Is it just for you, your family, a small business or a large company? A solo entrepreneur might be happy with a straightforward app, while larger businesses might need something that plays well with their existing systems. And don't forget about integrations – for example, your calendar should work seamlessly with your email, project management tools, and video conferencing platforms.
3. Investigate about the user interface. A cluttered app can be frustrating, while a well-designed one will improve your scheduling experience, and your customers’. Look for customization options to make it truly yours. Also, make sure it syncs across all your devices – you'll want to check your schedule whether you're at your desk or on the go.
4. Consider the learning curve and what support you’ll have. The more features the app has, the longer you might take to master it, thus the question: do you need all those features? Or maybe a simpler tool (or plan) can do the job? If you do need them, good customer support can make all the difference. By weighing these factors, you'll find a calendar app that not only meets your current needs but can also grow with you.
What's the most popular online calendar?
Google Calendar is widely considered the most popular online calendar due to its free availability and seamless integration with other Google services, especially if you’re looking for free simple things to organize your day. Its widespread use makes it a common choice for both personal and professional use, though in some cases you might want to go for Google’s paid plans.
Is there a better calendar app than Google Calendar?
While Google Calendar is excellent, "better" depends on individual needs. For Microsoft users, Outlook Calendar might be superior. Apple users might prefer Apple Calendar. For those needing advanced AI features, Motion could be a better choice. Zeeg might be preferable for those focused on external appointment booking.
What's the best personal calendar to use?
The best personal calendar varies based on individual preferences and needs. Google Calendar is a versatile choice for many due to its simplicity and wide integration. If you want a calendar focused on scheduling automation, then Zeeg is a top choice. It also integrates with other calendars. But other options, like iCloud Calendar or Outlook, are usually good quality.
What's the best calendar tool for businesses?
There are many great calendar apps for businesses, with some offering integrated scheduling. Zeeg stands out as a cost-effective, comprehensive, and secure solution that integrates easily with other business tools. It's an excellent choice for companies seeking all-in-one functionality. Other notable options include Calendly for its simplified scheduling, Google Calendar, or Microsoft Outlook.
Sources - all prices were last checked on October 9, 2024:
1. Google Workspace pricing
2. Microsoft 365 pricing
3. iCloud+ pricing
4. Motion pricing
5. Any.do pricing
