How to convert days to hours
Every day is 24 hours, so the conversion is a single multiplication:
Worked example: 25 d → 25 × 24 = 600 h.
Quick mental estimate: Multiply by 24: 25 × 24 ≈ 600 h (exact: 600).
Days to hours conversion table
| Days (d) | Hours (h) |
|---|---|
| 1 d | 24 h |
| 2 d | 48 h |
| 3 d | 72 h |
| 5 d | 120 h |
| 10 d | 240 h |
| 15 d | 360 h |
| 20 d | 480 h |
| 25 d | 600 h |
| 50 d | 1,200 h |
| 75 d | 1,800 h |
| 100 d | 2,400 h |
| 200 d | 4,800 h |
| 250 d | 6,000 h |
| 500 d | 12,000 h |
| 1,000 d | 24,000 h |
Values rounded to four decimals. For a value that is not in the table, use the converter above — it accepts decimals and negative numbers.
When you need this conversion
- Project planning and deadlines, where a duration given in one unit has to be turned into the granularity your schedule uses.
- Billing and payroll: hours worked converted into days, or a rate quoted per unit of time.
- Cooking, exercise, media durations and any timer set from a figure written in another unit.
Getting it right
The arithmetic is a single multiplication, so mistakes almost never come from the calculation itself — they come from the value that goes into it. Check that the figure you are converting really is in days and not in a neighbouring unit, and that you have not already converted it once.
Sanity-check the direction of the result before you use it. One day is 24 hours, so converting days to hours should make the number larger. If it moved the other way, the conversion was applied backwards — the reverse converter is one click away.
About the units
Day (d)
The day is 24 hours, or 86 400 seconds. Deadlines, rentals, leave and interest are counted in days.
Hour (h)
The hour is 60 minutes, or 3 600 seconds — one 24th of a day.
Frequently asked questions
How many hours are in 1 day?
1 day equals 24 hours. To convert any value, multiply the number of days by 24.
How do I convert days to hours in my head?
Multiply by 24: 25 × 24 ≈ 600 h (exact: 600).
Is the d to h conversion exact?
The factor is a standard rounded value; for most purposes four significant figures are more than enough.
How do I convert days to hours in Excel or Google Sheets?
Put the value in A1 and use =A1*24. Multiplying by the factor works in every spreadsheet, in any programming language, and on a basic calculator.
How many decimal places should I keep?
For everyday use two decimals are plenty. Keep four if the result feeds another calculation, and round only at the very end — rounding intermediate steps is the most common reason a result comes out slightly wrong.