Time Converter

How do I convert seconds, minutes, hours, days, weeks, months and years?

Use this free online time converter: type a number, choose the unit you have and the unit you want, then press the Convert button. It works with seconds, minutes, hours, days, weeks, months and years, and shows the answer on the page with up to six decimal places. Months and years use average lengths, explained below.

What does the time converter do and why is it useful?

Time is measured in a mix of bases: 60 seconds in a minute, 60 minutes in an hour, 24 hours in a day, 7 days in a week, and then months and years that do not divide evenly into days. Doing a sum such as "how many hours are in 3 weeks" or "how many seconds are in a year" in your head is slow and easy to get wrong.

This tool handles those sums. It is useful for planning projects, converting video or audio lengths, writing technical documents, checking timeouts and durations in code, or helping with homework. If you need the gap between two actual calendar dates, the date difference calculator is a better fit, and the age calculator works out ages from a birth date.

How does the converter work under the hood?

All conversions pass through a single base unit, the second. The value you enter is multiplied by the number of seconds in the source unit, then divided by the number of seconds in the target unit. This lets any unit be paired with any other.

The unit lengths are:

• 1 minute = 60 seconds.
• 1 hour = 3600 seconds.
• 1 day = 86,400 seconds.
• 1 week = 604,800 seconds (7 days).
• 1 month = 2,629,746 seconds, an average of about 30.44 days.
• 1 year = 31,556,952 seconds, an average of 365.2425 days.

The month and year values are averages, so they are not the length of any particular calendar month or year. The year average of 365.2425 days reflects the usual leap year pattern, and the month is that figure divided by 12. Results are rounded to at most six decimal places. Nothing changes as you type. The calculation runs only when you press Convert.

How do I use the time converter step by step?

1. Enter the amount of time you want to convert in the value field.
2. Select the starting unit in the first drop-down list.
3. Select the target unit in the second drop-down list.
4. Press the Convert button.
5. Read the result on the page. To try other numbers or units, change the fields and press Convert again.

What do real conversions look like? Worked examples

Each figure below is computed from the second-based values above.

Example 1: 2 hours to seconds

Input: 2, from hours, to seconds. Calculation: 2 x 3600. Result: 7200 seconds.

Example 2: 3 weeks to days

Input: 3, from weeks, to days. Calculation: 3 x 7. Result: 21 days.

Example 3: 1 year to days

Input: 1, from years, to days. Calculation: 31,556,952 / 86,400. Result: 365.2425 days. Choosing hours as the target gives 8765.82 hours, and months gives exactly 12 months.

Example 4: 90 minutes to hours

Input: 90, from minutes, to hours. Calculation: 90 / 60. Result: 1.5 hours.

Example 5: 1 month to seconds and days

Input: 1, from months, to seconds. Result: 2,629,746 seconds. Switching the target to days returns 30.436875 days.

Example 6: 10,000 seconds to hours and minutes

Input: 10000, from seconds, to hours. Calculation: 10,000 / 3600. Result: 2.777778 hours. Choosing minutes returns 166.666667 minutes.

How do the units compare at a glance?

Unit	In seconds
1 minute	60
1 hour	3,600
1 day	86,400
1 week	604,800
1 month (average)	2,629,746
1 year (average)	31,556,952

Where do the average month and year come from?

A calendar year contains 365 days, or 366 in a leap year. Over a long cycle of 400 years, 97 of them are leap years, which makes the average length 365 plus 97 divided by 400 days, or 365.2425 days. Multiplying by 86,400 seconds gives 31,556,952 seconds, the figure used by the tool. Dividing that by 12 gives the average month of 2,629,746 seconds, about 30.44 days.

These averages are useful when you want a single consistent number. They are less useful when you care about a specific month. February has 28 or 29 days, while July has 31, so a month on a real calendar will rarely match the average. If your task depends on exact dates, a date-based tool is the right choice.

How can I use time conversions in everyday planning?

Suppose a task is estimated at 90 minutes. Example 4 shows that this is 1.5 hours, which is easy to enter in a timesheet that works in decimal hours. A project of 3 weeks is 21 days, which you can compare against a calendar deadline given in days. A process that runs for 10,000 seconds lasts about 2.777778 hours, or roughly 2 hours 47 minutes.

The tool is also handy for sanity checks. If a document says a service stays cached for 2,629,746 seconds, you can paste that figure in, choose days as the target, and see it is about a month. If a licence runs for 8765.82 hours, you can see that it is about one year. Turning a large raw number into a familiar unit often reveals whether a setting is sensible or a typo.

Developers often store durations in seconds and show them to users in larger units. A quick conversion helps you choose readable labels, such as showing 7200 seconds as 2 hours. Teachers can use the same approach to build exercises that go from seconds up to years and back again, which makes the relationships between units easy to see.

Whenever you record a converted number, write the unit next to it. A bare 90 could be minutes, hours or days, and the unit is what makes the figure useful to the next person who reads it.

What tips help me get accurate results?

• Treat results involving months or years as estimates. Use them for planning, not for exact dates.
• For exact calendar spans, such as the days between two specific dates, use a date tool because real months have 28 to 31 days.
• To split a decimal result into parts, take the whole number first, then multiply the leftover fraction by the next unit. For 2.777778 hours, the 0.777778 part times 60 is about 46.67 minutes.
• Convert in one step from the original unit to avoid piling up rounded values.
• If you are working out hourly pay or a price per day, combine the result with the percentage calculator or a basic calculator.

What common mistakes should I avoid?

• Treating a month as 30 or 31 days. The tool uses an average of about 30.44 days, so one month will not equal exactly 30 days.
• Using 365 days for a year. The tool uses 365.2425 days, so 1 year is 365.2425 days, not 365.
• Reading decimal hours as hours and minutes. 1.5 hours is 1 hour 30 minutes, not 1 hour 50 minutes.
• Swapping the units. Check both drop-down lists before pressing Convert.
• Expecting live updates. The result is shown only after you press the button.

Who uses a time converter?

Project managers convert effort estimates between hours, days and weeks. Video editors and podcasters turn run times into seconds or minutes. Developers set timeouts and cache lifetimes in seconds. Teachers and students use it for science and maths problems, athletes compare race and training durations, and writers check figures such as how many hours are in a year before putting them in an article.

Is my data private?

Yes. Everything runs in your browser. The numbers you enter are never uploaded, saved or logged, and there is no account or history. Refreshing the page clears the form.

What are the limitations of this tool?

• It supports seven units. Milliseconds, decades, centuries and fortnights are not included.
• Months and years are averages, not calendar-accurate lengths.
• It does not handle time zones, daylight saving changes, clock times or dates.
• Results show up to six decimal places. It converts one value at a time, with no batch mode, copy button or downloads.

Frequently asked questions

How many seconds are in a day?

86,400.

How many days are in a year here?

365.2425 on average.

How many days are in a month here?

About 30.44 days, shown as 30.436875 in results.

How many hours are in a week?

168, which is 7 x 24.

How many hours are in a year?

8765.82 using the average year.

Why are months and years not whole numbers of days?

Real months vary in length and the year is not exactly 365 days, so the tool uses averages.

Can it tell me the time between two dates?

No. For that, use the date difference calculator.

Where can I find more utilities?

See the full list of free tools.

Turn any duration into the unit you need

Enter a duration, choose two units and press Convert. With clear second-based definitions and honest averages for months and years, the result is easy to check and ready to use in plans, documents or code.