How Time Zones Work in Online Appointment Booking

Time zones cause booking confusion when handled poorly.

The Problem

• Business in New York

• Customer in Los Angeles

• Calendar shows 2 PM

• Whose 2 PM?

Best Practices

Store in UTC:
All times stored as UTC internally.

Display locally:
Convert to user's timezone for display.

Be explicit:
Always show timezone with times.

Detecting User Timezone

JavaScript can detect browser timezone:
Intl.DateTimeFormat().resolvedOptions().timeZone

Displaying Times

Show times in user's timezone with clear label:
"2:00 PM Pacific Time"

Conversion

When booking:
1. User selects time in their timezone
2. Convert to UTC for storage
3. Convert to business timezone for calendar

Edge Cases

• Daylight saving transitions

• Ambiguous times

• Invalid times

Bookux

Bookux builds booking systems with proper timezone handling.

Related: Real-Time Availability · Clickable Time Slots