Developer

The Unix timestamp converter turns seconds since 1970-01-01 00:00:00 UTC into a labelled UTC time and the same instant in this browser’s local zone, or the reverse. A 13-digit value from Date.now() is treated as milliseconds. The page does not guess which zone a clock time was written in — you choose UTC or local.

It is not a calendar-day offset, not an Excel serial date, and not a leap-second clock. Adding “30 days from today” belongs on the date tools.

JSON, Base64 and URL encoding live under Utilities, with guides that say what each transform does and what it does not encrypt.