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# Extended Timezone Availability

The **Extended Timezone** feature gives you precise control over global scheduling. Instead of forcing every booking slot to follow one timezone, you decide exactly which timezones can see and book each slot. A client can only book a slot if they're in a timezone you've assigned to it.

| How it works

When you share your booking link, Cal ID quietly matches the right slots to the right person:

1. **Location detection:** the moment a client opens your booking page, Cal ID detects their timezone from their browser or location.
2. **Rule matching:** Cal ID checks the timezone rules you set on each slot.
3. **Smart filtering:**
* If the client's timezone **matches** a slot's assigned timezone, they see that slot, converted to their local time.
* If it **doesn't match**, Cal ID hides the slot — to them, you simply look unavailable during those hours.

| Set it up

|| Add multiple time slots

Break your day into distinct slots if you want to offer different windows of availability.

![](https://storage.crisp.chat/users/helpdesk/website/-/6/f/1/c/6f1c2c7b8034d000/image_nt945.png =1144x615)

* To add a slot to a day, click the **plus (+) icon** next to the time inputs.

|| Assign timezones to each slot

* Next to a time slot, click the **globe icon** to open the timezone dropdown.

![](https://storage.crisp.chat/users/helpdesk/website/-/6/f/1/c/6f1c2c7b8034d000/image_1azxyld.png =1136x615)

* Select the timezone(s) you want to target for that slot. You can pick several to cover a whole region (for example, multiple US or European zones).

![](https://storage.crisp.chat/users/helpdesk/website/-/6/f/1/c/6f1c2c7b8034d000/image_1cuz773.png =1144x615)

|| Save

* Click the blue **Save** button in the top-right corner to push your changes live.

| Examples

|| Split local and international hours

> **Scenario:** Your Monday availability spans **10:00 AM to 11:00 PM** locally, but you want to serve domestic and international clients at different times.
> * **Slot 1 (10:00 AM – 7:00 PM):** click the **globe icon** and select only **Asia/Kolkata**. Users outside India won't see this daytime slot.
> * **Slot 2 (7:00 PM – 11:00 PM):** add an evening slot, click its **globe icon**, and choose **America/New_York** or **America/Los_Angeles**.
>
> **Result:** a client in Mumbai only sees 10:00 AM–7:00 PM; a client in New York, opening the same link, only sees the evening options.

![](https://storage.crisp.chat/users/helpdesk/website/-/6/f/1/c/6f1c2c7b8034d000/image_b89daq.png =1150x615)

|| Target specific regions through the day

> **Scenario:** You're a London consultant focusing on European clients in the morning and Australian partners in the afternoon.
> * **Slot 1 (8:00 AM – 12:00 PM):** click the **globe icon** and check **Europe/London** and **Europe/Berlin**.
> * **Slot 2 (1:00 PM – 5:00 PM):** add an afternoon slot and select **Australia/Sydney** and **Australia/Melbourne**.
>
> **Result:** your calendar automatically sections off each client group — no cross-booking overlap or confusion.

![](https://storage.crisp.chat/users/helpdesk/website/-/6/f/1/c/6f1c2c7b8034d000/image_15ar0u1.png =1150x615)

| Why use extended timezones

* **Zero timezone math:** stop calculating time changes before sending links — Cal ID filters slots automatically by the booker's timezone.
* **Protect your energy:** talk to each international market only during the windows you've chosen to work.

| Related articles

* [**Create Availability in Cal ID**](https://help.cal.id/en/article/create-availability-in-cal-id-uk557v/)
* [**Multiple Time Slots per Day**](https://help.cal.id/en/article/multiple-time-slots-per-day-1hq8spx/)
* [**Multiple Schedules**](https://help.cal.id/en/article/multiple-schedules-1525u03/)