datetime-timezone

Store all datetime values in UTC in your database, convert local datetime inputs from the browser to UTC before sending to the API, and convert UTC timestamps back to the user's local timezone for display. This prevents misinterpretation of times across different systems and timezones.

datetime-local inputs from HTML forms represent local time without timezone information. Converting them to UTC ISO strings before API submission ensures the server stores an unambiguous, timezone-independent timestamp that won't be misinterpreted when retrieved or displayed to users in different timezones.

Standardize by storing all scheduled times as UTC in PostgreSQL, normalizing timezone-aware datetimes on the backend by stripping timezone data. When rendering reminders or due dates in the UI, convert UTC values back to the user's local datetime-local format for accurate, localized display.

Yes. The UTC storage and conversion pattern applies across frontend, backend, and API layers. TypeScript on both client and server can implement the same standardized workflow: store UTC centrally, convert to local on frontend display, and convert from local to UTC on submission.

Without normalization, timezone-aware datetimes stored directly in the database create ambiguity and inconsistency. Users in different timezones see incorrect times, scheduling conflicts occur, and API responses become unreliable. UTC normalization ensures a single source of truth across all systems.