Clock Time Rounding & Truncation
Round clock times to a chosen seconds interval using nearest, floor or ceiling, with midnight carry, adjustment reports and batch CSV or JSON export.
Ready. Explore the example or use the input controls to begin.
Scope and practical limits
1–1,000 times; input HH:mm or HH:mm:ss. Intervals 1–86,400 seconds measured from midnight. Nearest ties round forward. No date, timezone, DST, leap-second or payroll-policy interpretation.
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Using Clock Time Rounding & Truncation
Round clock times to a chosen seconds interval using nearest, floor or ceiling, with midnight carry, adjustment reports and batch CSV or JSON export.
- Start with the example and set the relevant dates, range or clock settings.
- Review validation messages and the calculated results, including calendar conventions and day offsets.
- Download JSON or CSV; where available, export all-day calendar events. Save a project to retain your inputs.
Example
08:07:30 rounded to the nearest 15 minutes becomes 08:15:00. 23:59:59 rounded to the nearest 15 minutes becomes 00:00:00 with day offset +1.
Questions & answers
What happens at midnight?
The clock display wraps to 00:00 while a separate day-offset field records the carry. The report also shows the signed seconds adjustment.
Can I use this as a payroll rule?
The tool performs arithmetic only. It does not determine which rounding policies are appropriate or legally permitted.
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