Case 1
- How much do you want to convert?
- 1
- From
- Years
- To
- Weeks
- How long is a year?
- Calendar average (365.2425 days)
52.1775
Open with these valuesTime Unit Converter
52.1775
Result: 52.1775Everything up to a week is exact. A year is not, so you choose: 365.2425 days on the calendar average, 365 in a common year, 366 in a leap year. One year is 52.1775 weeks on the average but 52.142857 in a common year, and a month here is one twelfth of that year — 30.436875 days, not 30.
Most-used pairs
each is its own pageDays to seconds1 day = 86,400 secondsHours to minutes1 hour = 60 minutesMinutes to seconds1 minute = 60 secondsDays to hours1 day = 24 hoursWeeks to days1 week = 7 daysYears to weeks1 year = 52.1775 weeks (calendar average)Years to hours1 year = 8,765.82 hours (calendar average)Months to days1 month = 30.436875 days (one twelfth of a year)
All 7 units
| Unit | Symbol | In second | Typical use |
|---|---|---|---|
| Second | second | 1 | The SI base unit of time |
| Minute | minute | 60 | Timers, cooking, short trips |
| Hour | hour | 3,600 | Working time, billing, schedules |
| Day | day | 86,400 | Deadlines, travel, notice periods |
| Week | week | 604,800 | Project planning, pregnancy |
| Month | month | 2,629,746 | Rent, subscriptions, contracts |
| Year | year | 31,556,952 | Interest, age, long-run planning |
The month and year rows use the Gregorian mean of 365.2425 days; a month is one twelfth of that. Switch the year basis above.
Day to Second
prints complete- 1 day
- 86,400 second
- 2 day
- 172,800 second
- 3 day
- 259,200 second
- 4 day
- 345,600 second
- 5 day
- 432,000 second
- 6 day
- 518,400 second
- 7 day
- 604,800 second
- 8 day
- 691,200 second
- 9 day
- 777,600 second
- 10 day
- 864,000 second
- 11 day
- 950,400 second
- 12 day
- 1,036,800 second
- 13 day
- 1,123,200 second
- 14 day
- 1,209,600 second
- 15 day
- 1,296,000 second
- 16 day
- 1,382,400 second
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Worked examples
Case 2
- How much do you want to convert?
- 1
- From
- Years
- To
- Hours
- How long is a year?
- Common year (365 days)
8,760.0000
Open with these valuesCase 3
- How much do you want to convert?
- 3
- From
- Weeks
- To
- Days
- How long is a year?
- Common year (365 days)
21.0000
Open with these valuesHow it's calculated
result = value × seconds per from-unit ÷ seconds per to-unit
- StepEnter the amount and pick the unit it is in.
- StepPick the unit you want it in.
- ResultIf months or years are involved, choose the year length that fits.
What this number means
The converter does one thing: it turns the amount you entered into seconds, then out of seconds into the unit you asked for. What it handles is a duration in the abstract, a quantity of time, rather than a span marked on a calendar — nothing here knows which months your span would actually cross. Up to a week both halves of that division rest on definitions: 60 seconds to a minute, 3,600 to an hour, 86,400 to a day, 604,800 to a week. Above a week they rest on the year basis you select. Follow the default settings. One year on the calendar average of 365.2425 days is 365.2425 times 86,400, or 31,556,952 seconds; divided by the 604,800 seconds in a week that comes to 52.1775 weeks. Switch to the common year and the sum becomes 31,536,000 divided by 604,800, or 52.142857. Take all four decimals as exact arithmetic on the definition you picked, not as precision about the world. That is also where the limit sits: the basis only reaches the result when a month or a year stands on exactly one side of the conversion. With both sides below a week — three weeks is 21 days — the choice changes nothing at all, and when a month faces a year it cancels out, since a year is 12 months on every basis.
Up to a week, everything is exact
Seconds, minutes, hours, days and weeks are fixed by definition: 86,400 seconds in a day, 604,800 in a week. Months and years are not, which is why you pick the year length yourself.
A month here is 30.436875 days
It is one twelfth of the year you selected, not a calendar month. No real month is that long, since February has 28 or 29 days and July has 31.
Pick the year that matches the question
The calendar average for interest, ageing and spans of many years where leap days accumulate. The common year for payroll periods, subscriptions and schedules planned against a real calendar.
Commonly misread
A year is 52 weeks.
It is 52.1775 weeks on the calendar average and 52.142857 in a common year — the familiar 52 weeks and 1 day.
A month is 30 days.
Here a month is one twelfth of the year you chose, so 30.436875 days on the calendar average.
This should match the days between two dates.
This converter scales an abstract duration, while a date calculator counts real calendar days. Three months here is 91.31 average days, but 15 March to 15 June is 92.
Reference table
| Unit | Seconds | Days (calendar average) |
|---|---|---|
| Minute | 60 | 0.000694 |
| Hour | 3,600 | 0.041667 |
| Day | 86,400 | 1 |
| Week | 604,800 | 7 |
| Month | 2,629,746 | 30.436875 |
| Year | 31,556,952 | 365.2425 |
Questions
How many weeks are in a year?
52.1775 weeks on the calendar average of 365.2425 days, 52.142857 in a common 365-day year — the familiar 52 weeks and 1 day — and 52.285714 in a leap year. Use the common year for scheduling and the average for long-run arithmetic.
How many hours are in a year?
8,760 hours in a common year, 8,784 in a leap year and 8,765.82 on the calendar average. Use 8,760 for anything billed or scheduled, because it is a whole number of real hours.
How many seconds are in a day?
86,400 — that is 24 × 60 × 60, exact by definition, and the figure this converter uses. Real days occasionally run a second longer when a leap second is inserted, but those are announced only months ahead.
How long is a month here?
One twelfth of the year you selected: 30.436875 days on the calendar average. No real month is that long, since February has 28 or 29 days and July has 31.
Which year length should I pick?
The calendar average for interest, ageing and anything spanning many years where leap days accumulate. The common year for payroll periods, subscriptions and schedules you plan against a real calendar. The leap year for one specific year such as 2028.
Why doesn't this match the days between two dates?
This converter scales an abstract duration; a date calculator counts actual calendar days, including whichever months and leap days fall in the span. Three months here is 91.31 average days, while 15 March to 15 June is 92.
Sources and last check
Information, not professional advice.