Time Unit Converter
1 week equals 604,800 seconds, and 1 year equals 31,536,000 seconds. This time unit converter changes seconds, minutes, hours, days, weeks, and years into one another using fixed standard relationships. Use it when you need a fast answer to questions like how many minutes are in a day, how many hours are in 3 weeks, or how many seconds are in half a year. Enter a value, choose the source unit, choose the target unit, and the result appears in the matching unit right away. Because each supported unit maps back to seconds, the conversion stays consistent for both whole numbers and decimals. That makes this tool useful for schedule planning, worksheet checks, uptime notes, study problems, and everyday reference lookups where the main job is converting duration, not interpreting a calendar.
Quick answer
The converter stores every supported unit as a fixed number of seconds, so any unit pair can be converted through the same base.
Result
31,536,000
What this tells you
- •The converter stores every supported unit as a fixed number of seconds, so any unit pair can be converted through the same base.
- •One minute is 60 seconds, one hour is 3,600 seconds, one day is 86,400 seconds, and one week is 604,800 seconds.
- •One year in this tool means 365 days, which equals 31,536,000 seconds, 525,600 minutes, and 8,760 hours.
- •Decimals work normally, so 1.5 hours becomes 90 minutes and 0.25 days becomes 6 hours.
- •The calculation uses the full unit factors first, then rounds the displayed answer to 6 decimal places for readability.
- •Swapping the from and to units reverses the same relationship, which makes quick answer checks easy.
How to Use
- 11. Enter the amount of time you want to convert. Whole numbers and decimals both work, including values like 2, 2.5, or 0.125.
- 22. Choose the unit you already have in the From field. Pick seconds for stopwatch values, hours for schedule blocks, days for longer spans, or years for rough annual comparisons.
- 33. Choose the target unit in the To field. For example, move from days to hours when building a timeline or from weeks to seconds when checking a formula.
- 44. Read the result shown below the form. The tool converts through seconds, then formats the final answer with commas and up to 6 decimal places.
- 55. Sense-check the output against the unit size. If 1 day does not come back as 24 hours or 1 year does not come back as 365 days, one of the selected units is probably wrong.
How It Works
Formula
converted time = value x (seconds in source unit) / (seconds in target unit)The formula uses seconds as the common base. First, multiply the input value by the number of seconds in the source unit to get a total in seconds. Next, divide that total by the number of seconds in the target unit. For example, 3 weeks becomes 3 x 604,800 = 1,814,400 seconds. Divide 1,814,400 by 86,400 and the result is 21 days. The same pattern works for every supported unit because the unit map is fixed: second = 1, minute = 60, hour = 3,600, day = 86,400, week = 604,800, and year = 31,536,000.
Calculation note: values are processed in the order shown above, using the current input units.
Worked Examples
How many seconds are in a year?
Start with 1 year and multiply by 31,536,000 seconds per year. The result is 31,536,000 seconds. This tool uses the common non-leap year assumption of 365 days, so the answer stays tied to a fixed annual unit instead of a calendar-specific year.
How many minutes are in a day?
One day contains 86,400 seconds. Divide 86,400 by 60 seconds per minute and you get 1,440 minutes. This is a common check for schedules, payroll summaries, and daily activity planning.
Convert 90 minutes to hours
Ninety minutes equals 90 x 60 = 5,400 seconds. Divide 5,400 by 3,600 seconds per hour and the result is 1.5 hours. This is the same as saying an hour and a half.
Convert 3 weeks to days
Three weeks equals 3 x 604,800 = 1,814,400 seconds. Divide 1,814,400 by 86,400 seconds per day and you get 21 days. This type of conversion is useful when a plan is written in weeks but a schedule needs daily detail.
Convert 0.5 years to days
Half a year equals 0.5 x 31,536,000 = 15,768,000 seconds. Divide 15,768,000 by 86,400 seconds per day and the result is 182.5 days. The decimal is expected because half of a fixed 365-day year is 182.5 days.
Convert 10,000 seconds to hours
Start with 10,000 seconds and divide by 3,600 seconds per hour. The exact value is 2.777777777..., which the tool displays as 2.777778 hours after rounding. This is useful when logs or timers store duration in seconds but you want a more readable hour value.
Common Time Conversion Reference
Use this table when you want a quick lookup for one full unit before entering a custom value into the converter.
| 1 unit | Seconds | Minutes | Hours | Days |
|---|---|---|---|---|
| Second | 1 | 0.016667 | 0.000278 | 0.000012 |
| Minute | 60 | 1 | 0.016667 | 0.000694 |
| Hour | 3,600 | 60 | 1 | 0.041667 |
| Day | 86,400 | 1,440 | 24 | 1 |
| Week | 604,800 | 10,080 | 168 | 7 |
| Year (365 days) | 31,536,000 | 525,600 | 8,760 | 365 |
The year row uses a fixed 365-day year. If your real use case depends on leap years, months, or date boundaries, use the table as a rough reference only.
When should you use fixed time conversions?
Fixed time conversions work best when the units themselves do not change. Seconds, minutes, hours, days, and weeks always keep the same length in standard time math. That makes them good for stopwatch readings, project estimates, content runtimes, server logs, class periods, shift planning, and quick unit checks in homework or documentation.
The choice of target unit depends on what you want to communicate. Seconds are useful for precise machine or timer data. Minutes and hours are easier to scan in schedules and human conversations. Days and weeks make longer plans easier to compare at a glance. A raw number like 172,800 seconds is technically correct, but 2 days is easier for most people to understand right away.
Years need more care because real calendars are not all the same length. This converter uses a fixed 365-day year because the formula file defines a year that way. That keeps the tool consistent and predictable. It also means the answer is best for unit conversion, not for exact date counting across leap years, leap days, or calendar-specific reporting windows.
Months are left out for the same reason. A month can have 28, 29, 30, or 31 days, so there is no single fixed month length that stays accurate in every situation. If you are converting calendar spans like billing cycles or due dates, use a date-based calculator. If you are converting pure duration with standard unit factors, this time unit converter is the right fit.
Common mistakes
- Choosing the wrong source unit. If a value is already in minutes but the form is left on hours, the result will be off by a factor of 60.
- Treating a calendar year and a fixed conversion year as the same thing in every context. This tool uses 365 days for a year, not a leap-year calendar count.
- Expecting months to convert cleanly like days or weeks. Months are not included because their length changes across the calendar.
- Rounding too early during a manual check. Keep the full value through the conversion, then round once at the end if you want the same display the tool shows.
- Ignoring unit size when reviewing the answer. If a larger starting unit produces a tiny target value or a small starting unit produces a huge target value, double-check that the from and to choices are not reversed.
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