Fastest way to find out who is available when

Zonio Freebusy service provides a simple and easy way to find out the availability of people without tedious phone calls, back and forth emails or organizing polls.

Get availability immediately

You will find and know the information you need immediately. There is no need to contact or remind anyone else to get it.

Stay focused

Others will be able to check when you are available on their own. No more distractions from what you are doing by calls asking you "When are you available?"

No need to sign-up

Just connect with your Google or Microsoft account and you will be good to go. Add your other emails to be discoverable on all addresses you use.

Features and benefits

Calendar discovery

We use robust calendar discovery process to find the availability for anybody who uses an online calendar and permits reading the availability information.

Multiple calendars

Connect multiple calendars and the availability will be calculated from all of them into single a unified view. Various calendar providers are supported.

Email as an identifier

People are identified simply by an email address - no special links or codes necessary. Any email address the person uses provides the full availability data.

Inverted availability

Do you need to treat your time differently? Be busy by default and let others to see you free in certain time slots only? Inverted availability allows that simply and without any calendar clutter.

Contacts loading

Contacts are loaded automatically together with calendars from Google, or Office365 to automatically suggest email addresses from the address book.


Simple to use API allows to personalise the content of applications and services based on availability context of their users. Check Developers page for more details.


Availability can be delivered through integrations directly into applications you use - calendars, phones and others. See Apps and integrations list for more options.

How it works

Connect primary calendar

First sign-in using your Google or Microsoft account and authorize Zonio Freebusy to access you calendar and contacts. When you sign-in your profile will be created. To keep you and your data safe and secure we do not request, get or store any of your passwords.

Add calendars or emails

Add other calendars you use to your profile and the availability will be calculated into a single unified view from all of them. Also add emails you use to let others discover your availability under any of your addresses.

Person selection

Type an email of person whose availability you want to know. Repeat for as many people as you would like. If you use the address book on your Google or Microsoft account, emails from these contacts will be automatically suggested for you.

Get the availability

We will discover a calendar and read free and busy time slots for each person and display it to you in a easy to read form on a timeline. Next refine the time range by scrolling, direct selection of a certain date or limiting the timeline to show work hours only.

Supercharge your application with availability context

Develop an application? You can personalise the content of your application by adding availability context similarly to user history or geo-location context. By using Zonio Freebusy API your app can create this context by requesting whether its user or people its user communicate with are available. The availability may be checked for persons or for the resources such as rooms and equipment.

Find out more about API