Pyas vs. Cronofy: Enterprise Scheduling Platform vs. Calendar API

The core difference

Cronofy is a scheduling platform. It syncs calendars across providers, and on top of that it offers availability rules, embeddable scheduling UI, booking pages, round robin, and meeting recordings and transcripts. Its pricing reflects that. The entry plan is $819 a month, billed annually, for up to 500 synced accounts.

Pyas is a calendar API. It gives your product one way to read and write events on Google Calendar, Microsoft 365 and Outlook.com, find free time, add Meet, Teams or Zoom links, and get webhooks when something changes. You build the screens and the scheduling logic your product needs. Pricing is monthly, with no contract, and starts free.

Both connect to users' calendars and both handle the sign-in. The difference is how much of the scheduling product comes in the box, and what you pay for it.

When Cronofy is the right choice

Cronofy fits when scheduling is the feature and you would rather embed it than build it. Its UI Elements include a Calendar Sync element for connecting accounts, an Agenda View, a Date Time Picker, a Slot Picker, Availability Rules and an Availability Viewer. The Embedded Scheduler adds booking pages, scheduling links and round robin. A team can ship a working booking flow without designing one.

It also fits when your users are on Apple iCloud or on-premises Microsoft Exchange.

When Pyas is the right choice

Pyas fits when you are building calendar features into your own product and want the calendar layer, not a scheduling product. A recruiting tool that books interviews on the recruiter's Outlook, a CRM that logs meetings from Google Calendar, a clinic app that adds a Zoom link to every appointment: these need events, free time, meeting links and webhooks, with the interface designed by the team that owns the product.

It also fits when price is a real constraint. At 200 connected accounts Pyas costs $75 a month. At 3,000 it costs $775. Cronofy's first paid tier is $819 a month billed annually, so a product with 200 accounts pays more than ten times as much there, before it knows whether the feature works. The price table above has the full comparison.

Who handles Google's review

Calendar scopes are sensitive in Google's eyes. An app that asks for them has to pass Google's OAuth verification before it can serve the public without warnings and user caps, and that review takes time. Microsoft has its own hurdle: many Microsoft 365 tenants require an administrator to approve calendar access for any app.

Cronofy takes Google's review off your plate. End users approve Cronofy's own Google and Microsoft apps, and Cronofy's docs say "There is no separate process required with Google or Microsoft to approve your application for production."

Pyas does the same with Pyas Auth, on every plan including the free one. Users approve Pyas on Google's, Microsoft's and Zoom's own consent screens, Google, Microsoft and Zoom have already verified it, and you skip Google's review. The difference is Native Auth: you can swap in your own Google or Microsoft app, per provider, so users see your product's name. You then own that provider's review. A bring-your-own-app option is not documented in Cronofy's docs.

What Cronofy does well

Cronofy's availability and free/busy endpoints find slots where groups of people and resources are free across providers, and its docs also cover Sequenced Availability.

The UI Elements include a slot picker and an availability rules editor you can embed.

Meeting Agents record Meet, Teams and Zoom calls and return a transcript and summary. Cronofy also offers Smart Invites.

Conferencing is one field: set profile_id to default and Cronofy provisions Meet or Teams to match the calendar, with Teams limited to work and school accounts. Zoom and GoToMeeting work once each user authorizes their account through a separate flow.

Cronofy ships official SDKs for Ruby, Node.js, Python, PHP and .NET. Enterprise Connect connects a whole organization's calendars through service accounts instead of one sign-in per person. And it has a hosted MCP server with tools to suggest times to meet, choose a suggested time and create a scheduling link, authenticated with a client secret or OAuth 2.0.

Where Pyas is different

Webhooks name what changed. Cronofy's push notifications are HMAC-signed and send a change type with a changes_since value. In Cronofy's words, "Your app can then query the Read Events or Free Busy end-points to get the latest changes." Pyas webhooks are signed too, and each one names the exact event or calendar that changed by its IDs, so your handler reads that one event. Failed deliveries are retried up to 8 attempts and can be replayed. Pyas renews Google push channels and Microsoft Graph subscriptions for you, and keeps no copies of users' events.

A sandbox with fake calendars. Cronofy's development mode uses up to 20 real accounts. Sample calendars are not documented in its docs. Every Pyas app has a sandbox of simulated Google, Outlook and Zoom accounts with sample people and real-looking calendars, reached with test keys that never touch a real calendar. The CLI streams sandbox webhooks to your laptop.

Events in one shape. Every event carries UTC, local time and the IANA time zone, across Google and Outlook. Recurring series and single occurrences are both addressable. Every write takes an idempotency key, and updates can carry If-Match so a stale edit is refused instead of overwriting a newer one.

Meeting times, not only busy blocks. Free/busy covers up to 20 accounts. The meeting times call returns the first times everyone is free inside working hours, with buffers, minimum notice, optional attendees and rooms, across Google and Outlook in one request.

Meeting links in one field. The conferencing field gives Google Meet on Google, Teams on Microsoft 365 work accounts and Zoom on any calendar through the host's connected Zoom account. Pyas creates the Zoom meeting. Teams on an Outlook.com personal account is refused with a clear error. More on the Zoom API page.

Account health you can show users. Each account reports its status, why it broke and the fix. A connection.broken webhook fires, and the status includes a userMessage you can show the user. They reconnect inside your app with PyasConnect and keep the same accountId.

AI agents with a read-only option. Pyas hosts an MCP server at mcp.pyas.io, added by URL with sign-in. The same server ships as @pyas/mcp on npm, which runs locally and has a read-only mode. @pyas/ai-tools exposes the same calendar actions to the Vercel AI SDK, LangChain, OpenAI and Anthropic tool use. Pyas runs no AI models itself. See calendars for AI agents.

Can you use both?

Rarely for the same users. Both would hold a connection to the same person's calendar, both would send you change notifications for it, and you would pay twice for one account. Pick one per product.

It can make sense across products or customer tiers. A company might serve an enterprise tier through Cronofy because those customers run on-premises Exchange, and serve a self-serve tier through Pyas because Cronofy's minimum does not fit a $20-a-month plan. That means maintaining two integrations, so do it only when the price gap or a hard requirement justifies it.

Questions to ask before you choose

• Do you need ready-made scheduling UI? If you want to drop in a slot picker, booking page or round robin, Cronofy has them. Pyas gives you the data and the actions, and you build the interface.
• Are any of your users on iCloud or on-premises Exchange? Cronofy supports both.
• How many accounts will you connect in year one? Under 500, Cronofy's entry plan is $819 a month billed annually. Pyas is $150 or less at that size.
• Do you want users to see your name on the consent screen? Pyas Native Auth allows it per provider. That option is not documented in Cronofy's docs.
• Which language is your backend in? Cronofy has SDKs for Ruby, Node.js, Python, PHP and .NET. Pyas has a TypeScript SDK today, with Python, PHP, Ruby and Go SDKs planned; any language can call its REST API meanwhile.
• How do you want to process changes? Cronofy tells you something changed and you query for it. Pyas tells you which event or calendar changed.

Moving from Cronofy to Pyas

Your users approved Cronofy's apps, so each one connects once more through PyasConnect, a dialog that opens in your own page and works in React, Vue, Angular or plain HTML. With the SDK, the session endpoint it needs is one line on your server. Their events never move. They stay in Google Calendar and Outlook, and Pyas reads them from there.

Build against the sandbox before you touch production. Point your event reads, writes and availability calls at test keys, and run your webhook handler against sandbox events streamed to your laptop with the CLI.

Then map your webhook handling. A Cronofy handler typically receives a change notification and queries Read Events with changes_since. A Pyas handler receives the IDs of the event or calendar that changed and reads that object. If you used Cronofy's Slot Picker or Embedded Scheduler, plan time to build those screens on Pyas's meeting times call. Users on iCloud or on-premises Exchange have no path on Pyas, so check your user base for them first.

Looking for a Cronofy alternative?

Start with what is not working. Cronofy's price and its scope are both deliberate, and the right alternative depends on which one is the problem.

If the price does not fit your stage

A product with 200 connected accounts pays $819 a month on Cronofy, billed annually, and $75 a month on Pyas, billed monthly. If you are early, or calendar sync is one feature among many, that gap decides it. Pyas's free Developer plan runs in production with 3 accounts, so you can launch to a pilot customer before paying anything.

If you want to build your own scheduling experience

If your product's scheduling flow is part of what you sell, embedded UI from another vendor may not fit your design. Pyas gives you events, free/busy and meeting times and meeting links as API calls, and your team builds the screens. See use cases for what teams build this way.

If you are building AI agents that use calendars

Both have hosted MCP servers. Pyas adds a local npm version with a read-only mode and tool packages for the major AI SDKs. See Pyas for agents.

Other options

• Pyas vs. Nylas
• Pyas vs. Apiroc
• Pyas vs. Unipile
• Pyas vs. Aurinko
• Building it yourself with the official Google Calendar API and Microsoft Graph. You own Google's OAuth review, Microsoft app registration, push channel renewal and the differences between the two providers' event models. Our Google Calendar API and Outlook Calendar API pages cover what that involves.

The bottom line

Cronofy sells scheduling as a product: embeddable UI, booking pages, round robin, recordings, iCloud and Exchange, from $819 a month billed annually.

Pyas is a calendar API for product teams who build their own features on Google Calendar, Outlook and Zoom. It handles sign-in, events, free time, meeting links and webhooks, and costs $75 a month at 200 accounts. If your team builds its own scheduling features, start in the sandbox.