Enter a Unix timestamp (or use the current time), choose to add or subtract, then specify days, hours, minutes, and seconds to offset. Your result shows the new Unix timestamp along with the human-readable date and time so you can verify the output at a glance.
Result Unix Timestamp
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Result Date & Time (UTC)
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Total Offset Applied
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Base Date & Time (UTC)
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A Unix timestamp is the number of seconds that have elapsed since January 1, 1970, 00:00:00 UTC (known as the Unix Epoch). It is a standard way to represent a specific point in time in computing, independent of time zones.
To add time to a Unix timestamp, simply convert your desired offset into seconds and add it to the original timestamp. For example, adding 1 hour means adding 3,600 seconds. This calculator handles the conversion for you — just enter days, hours, minutes, and seconds separately.
Select the 'Subtract (−)' option, enter the days, hours, minutes, and/or seconds you want to go back in time, and the calculator will deduct that total offset from your base timestamp. The result is the earlier Unix timestamp.
Yes — you can find your current Unix timestamp by checking online tools or running Date.now() / 1000 in a browser console. Paste that value into the Base Unix Timestamp field to offset from right now.
Any field left at 0 simply contributes nothing to the offset. For example, if you only fill in hours and leave days, minutes, and seconds at 0, only the hours offset is applied. This lets you do quick single-unit adjustments without any issues.
A negative Unix timestamp represents a date before January 1, 1970 UTC. If you subtract more time than the base timestamp contains, the result goes before the Epoch. Most modern systems support negative timestamps, but some older systems may not handle them correctly.
Each unit is multiplied by its second equivalent: 1 day = 86,400 seconds, 1 hour = 3,600 seconds, 1 minute = 60 seconds, and 1 second = 1 second. All four are summed to get the total offset, which is then added to or subtracted from the base timestamp.
Unix timestamps are always in UTC (Coordinated Universal Time) by definition, so the calculation itself is time-zone agnostic. The human-readable date displayed is shown in UTC. To get your local time, you would need to apply your UTC offset to the result.