Duration Conversion Calculator
Written by Thierno Sadou Diallo, formula verified per our methodology • Last checked on 9/5/2026
To convert a duration, it's brought back to a common unit (the second) then converted into the new unit. For example, 90 minutes represent 1.5 hours.
Explanation
Converting a duration amounts to multiplying the value by the factor that brings it back to seconds, then dividing by the target unit's factor — exactly what this calculator does, regardless of which pair of units is chosen among second, minute, hour, day, and week. These factors are exact, universal definitions (60 seconds per minute, 3,600 seconds per hour, 86,400 seconds per day, 604,800 seconds per week), with no approximation or variation by country, unlike units such as the month or year whose exact length in days varies. This calculator is handy for converting a travel time, a cooking recipe duration, a workout time, or any time measurement expressed in a unit that's inconvenient to work with mentally. To convert a time from 24-hour to 12-hour format rather than a duration, see our 24-hour to 12-hour time converter; to calculate a gap between two calendar dates, our date difference calculator.
Example: converting 90 minutes to hours
Inputs
Value: 90. Starting unit: minutes. Target unit: hours.
Calculation
90 minutes equal 90 × 60 = 5,400 seconds. Dividing by 3,600 (the hour factor) gives 1.5 hours.
Result
90 minutes represent 1.5 hours, that is 1 hour and 30 minutes.
Frequently asked questions
Why doesn't this calculator offer months or years?
Because the exact length of a month (28 to 31 days) and a year (365 or 366 days) isn't constant, unlike the second, minute, hour, day, and week, which all have a fixed, universal definition. Converting to months or years would require specifying a reference date, which is better suited to a date difference calculator.
How do I read a result with a decimal part, like 1.5 hours?
The decimal part represents a fraction of the unit: 1.5 hours corresponds to 1 hour and 30 minutes (0.5 × 60 minutes = 30 minutes), exactly like 0.25 days corresponds to 6 hours (0.25 × 24 hours).
Can this calculator convert several values at once?
No, it converts one duration at a time between two chosen units. For a series of values, the conversion must be repeated for each one — the link generated in the address bar after a calculation can be reused and edited to speed up subsequent conversions.