Choose the conversion direction. For timestamp input, explicitly select seconds or milliseconds. Seconds allow up to three decimal places; milliseconds must be integers. For dates, use YYYY-MM-DDTHH:mm:ss with an optional one to three millisecond digits and a required Z or ±HH:mm suffix. Results show the UTC date, seconds and milliseconds together.
Enter one item per line, up to 500 lines. Each line shows a result or error; blank lines also produce errors. Local dates use your device’s time zone and daylight saving rules; date input must still include Z or an explicit time zone offset.
Timestamp 0 corresponds to 1970-01-01T00:00:00.000Z; -1 second is one second earlier. Negative subsecond precision is preserved without truncation toward zero. Nonexistent dates, leap seconds and dates without a time zone are rejected. Date input uses a four-digit year. The timestamp range is ±8640000000000000 milliseconds. The current time comes from your device's clock.