Sync your app with the Calendar API

Build great scheduling features for your users with the Cronofy Calendar API

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One API, all calendars

Connect to your customers' calendars

Microsoft’s personal email hosting has had several names over the years: Hotmail, Live, and of course, its most recent name, is used by millions of people across the globe, meaning that if you want to reach your customers you have to integrate with it.

However, not every customer uses There will inevitably be customers who favour Apple Calendar or Google Calendar instead. Building integrations with each API individually costs time and money. Maintaining them costs even more.

A better way to build

Cronofy allows you to create features for multiple calendar services while only needing to work with one API.

Whatever you build with the Cronofy Calendar API will work with, Office 365, Microsoft Exchange, iCloud, and Google Calendar.

That means that you can create a more user-friendly experience with advanced functionality and a workload that’s five times less than if you’d worked with each API individually.

Real-time Calendar Sync

Cross-calendar synchronization

When you create an event in and invite someone who uses Apple Calendar or Google Calendar, two versions of the event are created. Should any changes be made, there’s no guarantee these will sync across. This could cause all sorts of confusion for your customers.

When events are made using Cronofy, it doesn’t matter what calendar service customers use. Everything updates in real-time, preventing any double-bookings or potential confusion.

Greater user privacy integration is limited because it offers an all-or-nothing approach to accessing customers’ calendar information. That means that you can either access all of their personal details, or offer them a lesser user experience but greater privacy.

With Cronofy, you can create a connection that can see when a user is free or busy without accessing this personal information. Users’ private data stays private but they also don’t risk double-booking themselves.

Free trial

Full calendar sync with Cronofy

Sync your software to iCloud, Google Calendar, Office 365, and even Microsoft Exchange calendars

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Cronofy also offers...


Personal support

We’re here to answer your questions and help with any problems whenever you need assistance.


Global environment

Cronofy has been built for easy integrations across all languages and services, not just Microsoft and Windows.


99.95% uptime SLA

Cronofy is highly reliable, with a minimum average uptime of at least 99.95% guaranteed.


Always in active development

The Cronofy API has been under active development since its creation, and we frequently release new features and list upcoming alpha features.


All-in-one API access

Get the full, Exchange, Office 365, iCloud and Google Calendar APIs all through Cronofy. Best of all, you only need one set of docs to make it happen.


Documentation for developers

Written by our own in-house development team, our API docs are logical, consistent, and concise. One set of Cronofy docs is all you need.


Optimized data handling

Security and privacy are top priorities, so businesses and end-users can rest assured that data is handled legally and safely for all parties above and beyond the API’s standard.


Synchronization and scalability

One user or one billion, Cronofy scales to your requirements. Advanced synchronization means calendars that are always accurate.


Finely-tuned privacy

The standard API requires a lot of work to meet minimum privacy and security standards. Cronofy’s better data modelling means peace of mind for developers, businesses, and end users.

Integrating with Cronofy was really straightforward. Their documentation and support are first-class. We were able to quickly and easily integrate calendar availability into our call scheduling feature without having to worry about setting up several disparate calendar service integrations.

Chris Yancey
Full Stack Engineer - UpCounsel

Explore our customer stories

Cronofy/ Calendar API FAQs

How do I get Calendar API access?

Sign up for a free Cronofy account and then follow our quick Getting Started tutorial that covers everything you need to know.

Where do I get my Calendar API key?

The Cronofy API key includes calendar API access as well as all the other major calendar APIs – sign in to your Cronofy account for instant access.

Is there a tutorial for using the API for Outlook Calendar?

We’ve developed a quick start guide: Getting started with the Cronofy Calendar API, along with several other tutorials to explain the details.

Build full calendar sync in your app

Sync your software to all major calendar providers.

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