Time Unit Converter
Convert a length of time between milliseconds, seconds, minutes, hours, days, and weeks as you type.
Time Unit Converter converts in your browser.
Convert between units of time
Turning a 2.5-hour meeting into minutes, a timeout in milliseconds into seconds, or a 100-hour project estimate into days: type the amount, choose the two units, and the result appears as you type, along with the same length of time in every other unit. Every unit here has a fixed length, so each conversion is exact — which is why calendar months and years, whose length varies, are left out.
How to use the Time Unit Converter
- Type the length of time. Decimals such as 2.5, thousands separators such as 10,000, and negative values are accepted.
- Choose the unit you are converting from and the unit you are converting to. Swap units flips them and keeps your value.
- Read the result, the conversion factor, and the same time in every other unit. Copy Result copies the main conversion; Reset returns to 1 hour in minutes.
The method
result = value × (seconds per From unit) ÷ (seconds per To unit)
1 s = 1,000 ms · 1 min = 60 s · 1 h = 60 min · 1 day = 24 h · 1 week = 7 days
Each unit is stored as a whole number of seconds (a millisecond is 0.001 s, an hour 3,600 s, a week 604,800 s), so converting is one multiplication and one division at full precision. Only the displayed result is rounded, to at most 10 significant digits. Results come out as decimals: 90 minutes is 1.5 hours, not “1 hour 30 minutes”.
| From | To |
|---|---|
| 2.5 h | 150 min |
| 90 min | 1.5 h |
| 1 d | 86,400 s |
| 1 wk | 168 h |
| 1,500 ms | 1.5 s |
| 10,000 s | 2.777777778 h |
| 100 h | 4.166666667 d |
Converted on your device
- The conversion runs in your browser as you type; nothing is sent to a server.
- The values you enter and the results are not sent to Looty Tools or stored.
- The converter area is masked from session-recording analytics, so what you enter isn’t captured in recordings.
Limitations
- Months and years aren’t included because their length depends on the calendar. Use the Date Difference Calculator for spans between dates.
- A day is always 24 hours. Days when clocks change for daylight saving time, and leap seconds, are not accounted for.
- Results are decimals of one unit. To add or split durations such as 1 h 45 min, use the Time Duration Calculator.
- Negative values are converted as ordinary arithmetic, which suits differences or offsets.
- Results are shown to up to 10 significant digits; very large or very small results switch to scientific notation.
Related calculators
- Date Difference CalculatorMeasure the span between two dates.
- Hours Between Times CalculatorCount the hours between two clock times.
- Time Duration CalculatorAdd or compare lengths of time.
Guides
- Seconds to Weeks ExplainedThe fixed ratios that link seconds, minutes, hours, days, and weeks, where 60, 24, and 7 come from, and quick ways to convert between them.
- Milliseconds to SecondsWhere milliseconds appear in code, timers, and media, how to convert them to seconds and minutes, and a table of common millisecond values.
- Days in a YearCommon and leap years, the Gregorian leap-year rule, average year lengths used in science, and why a year can’t be a fixed time unit.
Time Unit Converter FAQ
- How many seconds are in an hour, a day, and a week?
- An hour is 3,600 seconds (60 × 60), a day is 86,400 seconds (24 × 3,600), and a week is 604,800 seconds (7 × 86,400).
- How do I convert hours to minutes?
- Multiply by 60. For example, 2.5 hours is 150 minutes, and 0.75 hours is 45 minutes. To go from minutes back to hours, divide by 60.
- Why are months and years not included?
- Their length changes: a month has 28 to 31 days, and a year has 365 or 366. There is no single number of seconds or days to multiply by, so this converter sticks to units with a fixed length. For spans measured on the calendar, use the Date Difference Calculator or the Age Calculator.
- How do I turn decimal hours into hours and minutes?
- Keep the whole hours and multiply the decimal part by 60. The converter shows 90 minutes as 1.5 hours; 0.5 × 60 = 30, so that is 1 hour 30 minutes.
- Does a day always have 24 hours here?
- Yes. The converter uses the standard 24-hour day. On the days clocks change for daylight saving time, a local calendar day can last 23 or 25 hours, and occasional leap seconds are also ignored.
- Can I convert negative values?
- Yes. The conversion is ordinary arithmetic, so −90 minutes becomes −1.5 hours — useful for time differences or offsets.
- Are the values I convert sent anywhere?
- No. The conversion runs in your browser as you type. The values you enter and the results are not sent to Looty Tools or stored, and the converter area is masked from session-recording analytics. Refreshing the page resets it.
