Timezone Handling

Synced handles timezone conversions automatically so you never have to do mental math.

How It Works

  • Each user's timezone is detected from their browser or profile settings
  • All times in the UI are displayed in the viewer's local timezone
  • The heatmap shows availability aligned to each participant's business hours
  • API responses use ISO 8601 format with UTC offset

Time Format Preference

Users can choose between 12-hour (2:30 PM) and 24-hour (14:30) time format in Settings → Profile.

Common pitfall

When parsing dates in JavaScript, new Date("2026-01-20") is interpreted as UTC midnight. Use moment.tz(date, "YYYY-MM-DD", timezone) to parse dates in a specific timezone.

API

When using the API, always pass times in ISO 8601 format with timezone offset:

"startTime": "2026-02-25T10:30:00-08:00"  // Pacific Time
"startTime": "2026-02-25T18:30:00Z"       // UTC

Booking Links

When guests visit a booking link, times are automatically shown in their detected timezone. A timezone indicator is displayed: "Times shown in your timezone: America/Los_Angeles".