Date and Timezone Handling: Avoiding Common Pitfalls

Date handling is notoriously tricky. This guide covers best practices for working with dates across timezones.

Golden Rules#

1. Store in UTC: Always store dates in UTC in your database
2. Convert on display: Convert to user's timezone only for display
3. Use ISO 8601: For API communication

Storing Dates#

Displaying Dates#

Using date-fns with Timezones#

API Communication#

Common Pitfalls#

Storing User Timezone#

Date Calculations#

Testing Dates#

Store UTC, display local, use ISO 8601, and always be explicit about timezones.