Days to hours
Convert any number of days into hours — and back again — using the exact, fixed relationship 1 day = 24 hours. It is useful for project planning, billing by the hour, cooking and brewing times, or any task where a duration is given in days but you need it in hours.
How it works
The conversion is a single multiplication or division:
hours = days × 24 and days = hours ÷ 24
Type a value and the result updates instantly. Press Swap to flip the direction between days→hours and hours→days. Because the relationship is exact, there is no rounding error; fractional inputs like 1.5 days are converted precisely.
Reference table
| Days | Hours | Common context |
|---|---|---|
| 0.5 | 12 | Half a day |
| 1 | 24 | One full day |
| 2 | 48 | Two-day shipping |
| 3 | 72 | 72-hour cancellation policy |
| 5 | 120 | Working week |
| 7 | 168 | One week |
| 14 | 336 | Two weeks / fortnight |
| 30 | 720 | Typical month |
| 31 | 744 | 31-day month |
| 365 | 8,760 | Common year |
| 366 | 8,784 | Leap year |
Where this conversion comes up
Project management. Gantt charts and project tools often express task durations in days, while timesheet systems bill by the hour. Converting a 4.5-day task to 108 hours lets you check whether the time logged matches what was planned.
Medical and pharmaceutical contexts. Drug dosing intervals and clinical-trial durations are sometimes described in days but need to be converted to hours for precise scheduling. A 5-day course of a drug taken every 6 hours means 20 doses; 5 days × 24 ÷ 6 confirms this.
Brewing and fermentation. Many home-brewing guides specify primary fermentation periods (for example 7 days = 168 hours) and secondary conditioning times. Knowing the exact hours helps with timing hydrometer readings or temperature adjustments.
SLA and uptime calculations. Service level agreements often state response times in hours and resolution times in days. Converting keeps the units consistent when calculating whether a target was met.
Daylight saving note. This is a pure unit conversion based on the definition that one day equals exactly 24 hours. In real wall-clock terms, a clock-change day has 23 or 25 hours. This tool gives the exact mathematical conversion, not the clock time elapsed across a DST transition.
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