MODE
ELAPSED
24-hour clock • optional next day
NEXT DAY?
NO
For elapsed only
START (HH:MM)
S
Used for elapsed/add
END (HH:MM)
E
Used for elapsed/sub
DURATION (H)
h
Whole hours
DURATION (MIN)
m
0–59 (auto clamps)
CONVERT VALUE
V
Used in convert mode
UNIT
SEC
Convert to hh:mm and totals
WORKING
—
—
—
—
—
DURATION
READY
—
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MODE
ELAPSED
24-hour clock • optional next day
NEXT DAY?
NO
For elapsed only
START (HH:MM)
S
Used for elapsed/add
END (HH:MM)
E
Used for elapsed/sub
DURATION (H)
h
Whole hours
DURATION (MIN)
m
0–59 (auto clamps)
CONVERT VALUE
V
Used in convert mode
UNIT
SEC
Convert to hh:mm and totals
WORKING
—
—
—
—
—
DURATION
READY
—
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ELAPSED TIME
Convert both times to minutes
mins = 60×HH + MM
Then subtract
Δ = end − start
NEXT DAY
If end is next day, add 24h
end = end + 1440
Then do Δ = end − start
ADD / SUBTRACT
Duration in minutes:
D = 60h + m
Add: start + D
Subtract: end − D
WORKED ELAPSED
Start 09:15 → 555 min
End 14:05 → 845 min
Δ = 845−555 = 290 min
= 4h 50m
CONVERT UNITS
sec↔min↔hr↔day
1 min=60 sec
1 hr=60 min
1 day=24 hr
TIP
Use 24-hour times
Minutes auto clamp 0–59
Answer shown as hh:mm
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