⏱️ Time Unit Converter
By ToolNimba Editorial Team · Updated 2026-06-19
Type a value in any box and every other unit updates instantly. A year is treated as 365 days.
This time converter switches a value between milliseconds, seconds, minutes, hours, days, weeks, and years. Type a number into any box and every other unit updates at once, so you can see, for example, that 90 minutes is 1.5 hours or that 2 weeks is 336 hours. Everything runs in your browser, so nothing you type is ever sent anywhere.
What is the Time Converter?
Time units all relate to each other by fixed factors, which is what makes converting between them pure arithmetic. The second is the base unit in the metric (SI) system, and the others stack up from there: 60 seconds make a minute, 60 minutes make an hour, 24 hours make a day, and 7 days make a week. A millisecond is one thousandth of a second, the unit you most often meet when measuring how long code, a network request, or an animation takes.
The cleanest way to convert is to go through a single base unit. This calculator turns whatever you type into seconds first, then divides by the target unit. For instance, 3 days is 3 × 86,400 = 259,200 seconds, and dividing that by 3,600 gives 72 hours. Converting through one shared unit avoids the rounding drift you get from chaining lots of separate steps.
Years are the one unit without a single fixed length, which is why you should know the convention before you trust a number. A common calendar year is 365 days, a leap year is 366 days, and the average Gregorian year is about 365.2425 days. This tool uses 365 days for a year (31,536,000 seconds), which is the usual choice for quick estimates. If you need exact spans across specific calendar dates, including leap years, use a date difference calculator instead.
When to use it
- Converting a duration shown in seconds (such as a video length or a timeout setting) into minutes and hours.
- Working out how many hours or days a project measured in weeks actually represents.
- Reading a performance figure in milliseconds and seeing it in plain seconds.
How to use the Time Converter
- Type the value you have into the box for its unit, for example 90 in the Minutes field.
- Read the converted value from any of the other unit boxes, which update instantly.
- Clear or change the box to convert a new value; emptying the field resets the others.
- Switch which box you type in at any time to convert in the opposite direction.
Formula & method
Worked examples
Convert 90 minutes to hours.
- seconds = 90 × 60 = 5,400
- hours = 5,400 ÷ 3,600 = 1.5
Result: 90 minutes = 1.5 hours
Convert 3 days to hours and minutes.
- seconds = 3 × 86,400 = 259,200
- hours = 259,200 ÷ 3,600 = 72
- minutes = 259,200 ÷ 60 = 4,320
Result: 3 days = 72 hours = 4,320 minutes
Convert 2 weeks to days and hours.
- seconds = 2 × 604,800 = 1,209,600
- days = 1,209,600 ÷ 86,400 = 14
- hours = 1,209,600 ÷ 3,600 = 336
Result: 2 weeks = 14 days = 336 hours
Each time unit expressed in seconds
| Unit | Seconds |
|---|---|
| 1 millisecond | 0.001 |
| 1 second | 1 |
| 1 minute | 60 |
| 1 hour | 3,600 |
| 1 day | 86,400 |
| 1 week | 604,800 |
| 1 year (365 days) | 31,536,000 |
Common conversions at a glance
| From | Equals |
|---|---|
| 1 hour | 60 minutes |
| 1 day | 24 hours = 1,440 minutes |
| 1 week | 7 days = 168 hours |
| 1 year | 365 days = 8,760 hours |
| 1 year | 525,600 minutes |
| 1 year | 52.142857 weeks |
Common mistakes to avoid
- Treating a year as exactly 52 weeks. 52 weeks is only 364 days, one day short of a 365-day year. A year is about 52.14 weeks, so rounding to 52 quietly loses a day over the span.
- Mixing up milliseconds and seconds. A millisecond is one thousandth of a second, not one hundredth. 500 ms is 0.5 seconds, and 1,500 ms is 1.5 seconds. Slipping a factor of ten or a thousand here is a frequent timing bug.
- Expecting calendar-accurate year spans. This tool uses a fixed 365-day year, so it does not account for leap years or specific start and end dates. For exact spans between two real dates, use a date difference calculator instead.
Glossary
- Second (s)
- The base unit of time in the metric (SI) system. Every other unit here is defined as a multiple or fraction of it.
- Millisecond (ms)
- One thousandth of a second (0.001 s). Common when measuring software, network, and animation timing.
- Conversion factor
- The number of seconds in one of a given unit, used to convert to and from that unit. For minutes it is 60, for hours 3,600.
- Calendar year
- A common year of 365 days or a leap year of 366 days. This tool uses the 365-day common year for conversions.
Frequently asked questions
How many seconds are in a minute?
There are 60 seconds in a minute. To go the other way, divide a number of seconds by 60 to get minutes, so 300 seconds is 5 minutes.
How do I convert seconds to minutes?
Divide the number of seconds by 60. For example, 5,400 seconds ÷ 60 = 90 minutes. To convert minutes back to seconds, multiply by 60 instead.
How many hours are in a day, and how do I convert hours to days?
A day has 24 hours, so to convert hours to days you divide by 24. For example, 72 hours ÷ 24 = 3 days, and 3 days × 24 = 72 hours.
How long is a year in this converter?
A year is treated as exactly 365 days (31,536,000 seconds). That makes it 8,760 hours or 525,600 minutes. Leap years and specific calendar dates are not taken into account.
How many milliseconds are in a second?
There are 1,000 milliseconds in one second. So 500 ms is 0.5 seconds and 2,500 ms is 2.5 seconds. A millisecond is one thousandth of a second.
Is this time converter free and private?
Yes. It is completely free with no sign-up, and all the maths runs in your browser. Nothing you type is uploaded or stored, so your values stay on your device.