Calendar APIs allow businesses to integrate applications with calendars across service providers, such as Microsoft Outlook and Google Calendar. Without calendar APIs, manually building scheduling connectivities within an app or website exhausts resources and time.
Using calendar APIs means development teams can focus on building mission-critical features that maximize adoption and retention. Businesses can save time while increasing scheduling productivity for their end users and easily capture valuable insights.
But determining which calendar API will best optimize your scheduling workflows can be difficult. So today, we’ll cover the best calendar APIs on the market so you can find the right one for your business.
A calendar API allows developers to integrate calendar functionality into their applications and websites. With the help of calendar APIs, developers can easily centralize scheduling workflows within a platform, enabling users to create and manage calendar events, invite attendees, sync calendars, set reminders, and more.
However, not all calendar APIs are created equal. Well-designed calendar solutions for embedding scheduling capabilities in an application or website should offer a wide range of customization options to fit unique business needs.
But many calendar APIs are missing crucial capabilities that can roadblock your integration efforts. For example, while some calendar APIs offer a free/busy resource showing a single user’s availability, you may not be able to compare the availability of multiple individuals easily.
Similarly, if you want to find availability for multiple meetings with several participants, without the right calendar solution, this functionality can require additional development effort and custom code.
To avoid spending invaluable developer time and resources, you’ll want to opt for a calendar API that offers availability endpoints. Doing so will allow users to see shared availability across multiple parties, both internal and external, to an organization. And consecutive availability endpoints provide time slots across participants for multiple, consecutive meetings.
Availability is just one example of features you may be looking for out of a calendar API. When looking for the best calendar solution, it’s important to consider the needs of your users.
Below we’ve outlined the top calendar APIs on the market, highlighting how they work, key features, and pricing structures to help you determine the best fit for your organization.
How it works: The Nylas Calendar API is the best solution for developers to connect their applications to all major calendar providers using a single point of integration. It provides developers the flexibility to quickly and securely build integrations and customize workflows for your users, offering an end-to-end scheduling solution. By helping users automate their scheduling workflows, the Nylas Calendar API creates a seamless user experience in your app which can increase retention and CSAT.
The Nylas platform goes beyond calendar connectivity and scheduling with a powerful suite of communications integration solutions, including email and contacts APIs.
Key features:
Pricing:
Nylas offers a full-service API platform, including an email API, calendar API with a front-end scheduler, and contacts API. Pricing plans vary by the number of connected accounts (end users).
Talk to an expert today to choose the best plan for your business.
How it works: Cronofy’s calendar API allows developers to connect their applications with multiple calendar service providers, such as Google Calendar and Apple Calendar. The API provides developers with guides and SDKs to assist them in navigating the platform. One of the key features of the Cronofy Calendar API is its real-time availability, which helps users avoid scheduling conflicts.
The API also includes UI elements that can be embedded into an application and the ability to send out calendar invites with video conferencing details.
Key features:
Pricing:
Cronofy offers annual and monthly pricing packages for their API and scheduler separately.
How it works: Calendly enables users to automate appointment and meeting scheduling. It offers a REST-based API that allows businesses to retrieve Calendly links, report on scheduled meetings, and retrieve availability for a specific event type for team members within an organization. The platform also has an Embed API, which lets businesses add a user’s Calendly scheduling page to their websites by enabling inline, pop-up text, or pop-up widget variations.
Calendly’s API is read-only, intended to make it easier for businesses to embed calendar functionality on web pages. For example, it can only read the free/busy status of events in users’ calendars. For organizations looking to extract scheduling data, you’ll want to consider an API that uses event metadata to drive deeper insights.
Key features:
Pricing:
Calendly is primarily feature-based and offers four pricing models:
How it works: The Google Calendar API allows for the creation, reading, updating, and deletion of calendar events, as well as the management of calendar settings and the reading of calendar metadata. The API helps handle single or recurring events, calendar management, user preferences, and access control rules.
Google’s calendar API follows RESTful principles and can be accessed via explicit HTTP calls or through the use of Google Client Libraries. The API uses OAuth 2.0 for authentication and supports multiple programming languages.
Key features:
Pricing:
As a support tool, Google Calendar is free to use. However, it doesn’t have as many features or capabilities as other paid options, like Nylas.
How it works: Zoho Calendar is a calendar and scheduling platform that is part of the Zoho suite of productivity and collaboration tools. The platform brings all calendars to one place and enables organizations to collaborate and manage events, appointments, and bookings. The Zoho Calendar API enables developers to customize features in the Zoho Calendar, and integrate the calendar with your application.
Key features:
Pricing:
While Zoho Calendar is free, pricing for the Zoho Calendar API is not listed online.
How it works: AddEvent is a platform that enables developers to add events to users’ calendars, collect information from attendees during registration, share multiple events through a subscribable calendar, and embed a calendar on a website.
AddEvent offers both a calendar API and an event API. The calendar API makes it easy for end-users to create, save, and delete calendars, view and delete subscribers, create, save, and delete events, and list all events across all calendars. The event APIs also allow users to create, save, and delete events, as well as manage RSVPs, list events, and manage time zones.
Key features:
Pricing:
AddEvent offers four annual pricing plans:
How it works: Timekit’s API allows developers to create resources, sync calendars, manage projects, and control booking flows. Users can customize their interface and manage bookings through their booking.js kit, which contains various blueprints. The Timekit API also utilizes webhooks for their booking process, which provides users with a real-time view of changes that happen to a booking.
Key features:
Pricing:
Timekit offers four pricing levels:
How it works: The Cal.com API provides access to data models that allow developers to build calendar features into their own applications, including availability displays and specific event mapping. The API allows users to manage teams on self-hosted platforms.
Key features:
Pricing:
Cal.com offers four pricing categories:
How it works: The Microsoft Outlook Calendar API is a solution that caters to personal, educational, and business services. It’s linked with Outlook email services and helps users integrate and manage calendar events and appointments.
The Outlook Calendar API is synced with other Microsoft 365 products and enables access to phone and email contacts, as well as OneDrive.
Key features:
Pricing:
Microsoft Outlook calendar API is free for personal use but offers a subscription-based model for the business and education sectors.
Are you looking to further narrow down your options? We’ve categorized the top calendar APIs by integrations below.
The best calendar API is going to depend on what your business is looking for. If you need to quickly add scheduling and other calendar capabilities to your business application – while saving your developers thousands of hours of building time – Nylas is the top choice.
Try out the Nylas Calendar API today and revolutionize how you get things done.
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