Time unit converter
Convert seconds, minutes, hours, days, weeks, months and years. The calculator shows the multiplier between the units next to the answer.
90 minute (min) is 1.5 hour (h).
Formula
x is the input value and k the multiplier. Every unit is converted into seconds first.
How we got there
A month is taken as 1/12 of a year and a year as 365.25 days, the same convention scientific calculators use.
How to convert time units by hand
- Convert the value into seconds
The second is the base unit. 1 min = 60 s, 1 h = 3600 s, 1 day = 86,400 s.
- Divide by the target unit
To get hours from minutes, divide the seconds by 3600. For 90 minutes that gives 1.5 hours.
- Mind the months and years
Months vary in length, so the calculator uses an average based on a 365.25-day year.
Want to practise more conversions? a lesson with a Mathema tutor
Frequently asked questions
An hour and a half. 90 ÷ 60 = 1.5.
Eighty-six thousand four hundred — 24 × 60 × 60.
As 1/12 of a 365.25-day year, which is about 30.44 days. That keeps year and month conversions consistent.
Unlock the Mathema lesson library
Leave your email and phone — we will take you through to the Mathema platform and open up the preparation library: problem sets, quizzes and lesson plans written by teachers.
Units to master?
Book a free introductory lesson with a Mathema tutor. 30 minutes online, no commitment — we find the gap and the plan to close it.