Time Converter

Convert between seconds, minutes, hours, days, weeks, months and years.

What the Time Converter does

Time conversion is exact up to weeks. Months and years vary in length, so this converter uses the average month (30.44 days) and the Julian year (365.25 days), which includes leap years.

Formula

  • Convert to second, then divide by the target unit's factor
  • Result = Value × (from factor ÷ to factor)

Inputs explained

InputUnitRequiredNotes
ValuenumberYes
Fromone of 9 optionsYes
Toone of 9 optionsYes

How to use it

  1. Choose From and To.
  2. Enter Value.
  3. Select Calculate.

Worked example

Convert 3.5 hours to minutes.

Value
3.5
From
Hour
To
Minute

3.5 × 60 = 210 minutes.

Reading the result

  • Conversions up to weeks are exact. Anything expressed in months or years is an average, so treat those results as estimates rather than counts.

Assumptions and limitations

  • A month is taken as 30.44 days and a year as the Julian year of 365.25 days, which averages leap years in.
  • This is arithmetic on durations, not on the calendar. Use the date difference calculator when the answer has to land on a real date.

Common mistakes

  • Scheduling real dates from average months. Thirty-six average months and three calendar years do not end on the same day.
  • Assuming a year is exactly 365 days where precision matters — the missing quarter-day is what leap years exist to absorb.

Frequently asked questions

Why is a month 30.44 days?

It is the average calendar month: 365.25 days divided by 12. Individual months range from 28 to 31 days.

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