The Best Nylas Alternatives in 2025

Nylas is one of the most popular unified API products, offering solutions for email API, Calendar API, contacts API, notetaker API, and more.

In this article, we’ll explore the best Nylas alternatives, focusing on platforms that cover a subset of the solutions or 1:1 replacements, including pricing and things to consider.

What are the best Nylas alternatives in 2025?

1. OneCal Unified Calendar API - For Calendar API

OneCal is one of the most popular Calendar Synchronization and scheduling tools in the market, used by thousands of professionals across all major industries. Users use OneCal to sync their calendars across Google Calendar, Outlook, and iCloud Calendar, share intuitive scheduling links with others, and view all their calendars in one view.

The vast experience with calendars and the reliability of the platform have prompted many users and companies to ask if a unified calendar API is available to the public, so they could leverage it to integrate multiple calendar providers using a single API.

The good news is that OneCal is launching its Unified Calendar API product, focusing on the following features:

• iCloud Calendar, Outlook, and Google Calendar integrations: Using the OneCal Unified Calendar API, you’ll be able to integrate all calendar providers into your applications using a single API.
  
• Support for webhooks: Taking actions based on changes in a calendar is crucial for most applications, that’s why the OneCal Unified Calendar API supports webhooks out of the box. Another reason for supporting a unified way to handle webhooks is that all calendar providers offer support for webhooks. If you integrate with iCloud Calendar, you have to implement your own solution to detect changes in iCloud Calendar. Using OneCal Unified Calendar API, you can register your own webhook in the platform and get notified of changes in calendars, regardless of the calendar provider.
• Generic Calendar APIs: The OneCal Unified Calendar API is generic, allowing you to build any type of application, from scheduling to calendar apps.
• Reasonably priced: Although our pricing is not public yet, we’re making efforts to come up with the most competitive pricing in the industry, making it reasonable for companies to use our product without costing a fortune.

2. Cronofy - For Calendar/Scheduling API

Cronofy is a Nylas alternative, focusing only on Calendar and Scheduling APIs and a flatter pricing, as opposed to the per-connected-account pricing Nylas has.

Cronofy Features

• Support for iCloud Calendar, Google Calendar, Microsoft Exchange, and Outlook.
• Calendar API: Using Cronofy, you can read and write to all major calendar providers.
• Scheduling API: Aside from the Calendar API, you can use Cronofy to easily build custom scheduling solutions and embed them into your application.
• Support for webhooks: You can receive push notifications using Cronofy, allowing your app to be notified when changes occur to calendars.
• SOC2, GDPR and other related certifications: Cronofy is SOC2, ISO27001, and ISO27018 compliant.

Cronofy Cons

• High initial pricing: Nylas charges per connected account (starting from $0.90 per connected account/month). The Cronofy Calendar API product, on the other hand, starts from €749 per month. Each pricing model has its pros and cons, but if you’re a small startup starting out, Cronofy has a higher starting price point.

Cronofy API Pricing Page:

3. Unified.to - For Calendar API, Communications API

Unified.to is a new to the market unified API product that offers solutions for Unified Calendar API, Unified Communication API, and tens of other APIs.

Unified.to Features

• Support for Google Calendar, Outlook, iCloud Calendar, and more.
• Support for CRUD operations. You can CRUD events, calendars, and links. You can query the busy slots and recording.
• Messaging API: Support for Gmail, Teams, Slack, and other messaging integrations.

Unified.to Cons

• Partial support for webhooks: Unified.to doesn’t support Push Notifications/Webhooks for all calendar providers yet. You’ll need to register webhooks for Google Calendar/Outlook to Unified.to, and implement your own polling solution for iCloud Calendar or other providers that don’t offer native push notifications.
• Expensive to get started: Unified.to offers a Test plan that you can use to test the integrations before getting started. The cheapest paid plan starts from $350 per month, which is a higher pricing point compared to Nylas. If you exceed 50,000 monthly API calls, you’ll have to jump to the Grow plan, which starts from $750 per month.

Unified.to Pricing Page:

4. Unipile - For Calendar and Email Integration

Unifile is a Unified API product that focuses on messaging & scheduling.

Unipile Features

• Support for Google Calendar and Outlook.
• CRUD for Calendars and events. You can list all calendars, get a single calendar, and CRUD calendar events.

Unipile cons

• No support for webhooks: Unipile doesn’t support webhooks for calendars yet. To date, you can only register webhooks to track new emails or new messages.
• No support for iCloud or other calendar providers.
• More expensive than Nylas: Similar to Nylas, Unipile charges per connected account, but it’s more expensive than Nylas. If you have 11-50 accounts, the pricing is $5.50 per account per month. The lowest price per account is $3.50, but you need to connect 5001+ accounts.

Unipile Pricing Page:

5. EmailEngine - For email integration

EmailEngine is a self-hosted Email API solution that helps developers connect with IMAP, SMTP, Gmail API, and Microsoft Graph API.

EmailEngine Features:

• CRUD for Mailbox, Messages, and more: You can use HTTP calls to manage your mailbox, get messages, attachments, and more.
• Webhook notifications: EmailEngine sends you a webhook notification every time there is an update on an email account.
• OAuth2 integration: You can integrate with Outlook or Gmail using OAuth2, with the option to renew the connection yourself or let EmailEngine do it for you.
• Monitor your usage via Prometheus: You can use Prometheus to monitor your email performance, including metrics like sending queues, webhook queues, cache hits, etc.
• Flat pricing: EmailEngine only has one plan, $995 per year.

EmailEngine Pricing Page

Which platform is the best Nylas alternative?

The best Nylas alternative will depend on the integrations you are trying to use in your applications.

If you’re trying to integrate with all major calendar providers, the OneCal Unified Calendar API is worth giving a shot.

If your use case involves embedding a customizable scheduler on your landing page, Cronofy is a great alternative.

For email integrations, Unified.to. and EmailEngine are great alternatives.

Use the OneCal Unified Calendar API to integrate all your calendar providers using a single API

Join our Unified Calendar API waitlist to get notified as soon as we launch the product and benefit from the early launch discounts.