Unix Timestamp Converter

Unix time counts elapsed seconds since January 1, 1970 at 00:00:00 UTC, also called the epoch. It is compact, timezone-neutral, and common in logs, APIs, databases, analytics events, queues, schedulers, and distributed systems. JavaScript often uses milliseconds, while many APIs use seconds, so digit count matters when debugging timestamps.

This converter auto-detects seconds versus milliseconds, shows local time, UTC, ISO 8601, and a human relative description. It also converts a chosen local date and time back into both second and millisecond timestamps. The live banner updates every second for quick copying during tests.

The Year 2038 problem affects old 32-bit systems that store signed epoch seconds. Modern browsers and most 64-bit services can represent much larger dates, but legacy databases, embedded software, and older APIs may still have limits worth checking.