A time recorded in Korea
Choose KST for Korean reservations, payments and delivery records. Korea currently has no seasonal clock changes.
Date to Unix time
Convert a date to a
Unix timestamp
Choose a calendar date and time, then specify whether that clock reading is UTC, Korea Standard Time or your current device time. See the same instant as seconds, milliseconds, microseconds and nanoseconds.
How to choose the time-zone basis
A timestamp is one time-zone-independent number. When creating that number from a calendar date, the converter must know which regional clock the input represents.
A time marked Z or UTC
Choose UTC when a record explicitly says UTC or ends in Z. This is common when comparing records from several countries.
A time selected on this device
Choose device time for a local schedule that should follow your current regional setting. Confirm that the device setting is correct.
The same 2024-01-01 00:00:00 produces different results. Interpreted as UTC it is
1704067200 seconds; interpreted as KST it is 1704034800. The difference is exactly 32,400 seconds, or nine hours.Known date-to-timestamp values
These widely used boundary dates help verify both unit and time-zone selection.
| Date and basis | Unix seconds | Unix milliseconds | Meaning |
|---|---|---|---|
| 1970-01-01 00:00:00 UTC | 0 | 0 | Unix epoch |
| 1970-01-01 09:00:00 KST | 0 | 0 | The same instant in Korea |
| 2000-01-01 00:00:00 UTC | 946684800 | 946684800000 | Useful verification value |
| 2038-01-19 03:14:07 UTC | 2147483647 | 2147483647000 | Maximum signed 32-bit seconds |
Before using the seconds or milliseconds result
Check which unit the destination expects. The same instant has very different digit lengths in different units.
Integer seconds
Present-day values are generally about 10 digits. Decide whether to truncate or round fractional seconds according to the destination's rules.
Milliseconds
The converter preserves the milliseconds selected in the calendar input. Present-day values are generally 13 digits.
Microseconds and nanoseconds
The date field accepts precision through milliseconds, so finer-unit results end in zeros. More digits do not create additional measurement accuracy.
Seasonal changes in device-local time: some regions skip or repeat a clock hour. For an important ambiguous time, use an explicit offset in the ISO 8601 validator.
Date conversion questions
Common questions about the meaning of the input clock and output units.
Why do UTC and KST produce different timestamps for the same clock reading?
The clock reading is interpreted in different time zones. KST is nine hours ahead of UTC, so the resulting instants differ by exactly 32,400 seconds.
What time should I enter if I only know the date?
Use 00:00:00 if you mean the start of that date, and select the time zone in which that date was recorded.
Why can the seconds result contain a decimal fraction?
When the selected time includes milliseconds, the result in seconds includes the same precision as a fractional part.
What does current device time zone mean?
The input is interpreted using the regional time-zone setting of your device. Choose UTC or KST explicitly if the device setting may not match the intended region.
Verify the converted value
Turn the generated number back into a date or compare it with the current value.
Convert back
Timestamp → date
Confirm that the number represents the intended UTC and KST date.
Convert to date →Compare with nowCurrent Unix time
See the current seconds and milliseconds immediately.
View current time →Check the offsetUTC ↔ KST
Compare how the intended date appears in both time standards.
Convert time zones →