Description
Add shiftMinutes to minuteOfDay.
Clock arithmetic wraps at the end of a day. A fixed offset can move a time into a prior or following day without implying any timezone or daylight-saving rule.
Add shiftMinutes to minuteOfDay.
When to use this tool
Use Navigation Watch Time Midnight Carry when you need an explicit clock offset or elapsed watch-time calculation.
How to use the tool and how it works
- Enter minuteOfDay, shiftMinutes. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read minuteOfDay, dayCarry. Use the output convention below.
Add shiftMinutes to minuteOfDay. Reduce modulo 1440 for the clock minute and use floor division by 1440 for signed dayCarry.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| minuteOfDay | Minute Of Day | Required. Safe integer; minimum 0; maximum 1439. |
| shiftMinutes | Shift Minutes | Required. Safe integer. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| minuteOfDay | Minute Of Day | Required. Safe integer. |
| dayCarry | Signed number of whole day boundaries crossed. | Required. Safe integer. |
{
"input": {
"minuteOfDay": 1380,
"shiftMinutes": 120
},
"output": {
"minuteOfDay": 60,
"dayCarry": 1
}
}Limitations and assumptions
- This is fixed minute arithmetic without dates, timezones, or watch-scheduling rules.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use a timezone-aware calendar library when real dates, daylight-saving changes, or civil-time scheduling matter.
References
Similar or alternative tools
- Family Contact Safe Clock Offset
Add integer offsetMinutes to the supplied hour and minute using exact integer arithmetic.
- Nautical Watch Bell Half Hour Index
For minutesSinceWatchStart in 0-240, return floor(minutes / 30) as bells, with zero before the first half-hour.