Screen time calculator
Enter your average daily screen hours, how many hours you are awake, your age and the lifespan you want to assume. The calculator shows hours per week and year, the share of your waking day, and how many years that adds up to over the years you have left. It only does the arithmetic and makes no judgement.
Runs in your browser: nothing you enter is sent anywhere.
How to use it
- Enter your average screen hours per day.
- Enter the hours you are awake, your age and the lifespan you want to assume.
How it works
Share = screen hours ÷ waking hours. Per week is hours × 7 and per year is hours × 365. Years left is lifespan minus age, then waking years = hours × years left ÷ waking hours.
Worked example
4 hours a day, 16 waking hours, age 30, lifespan 80: 25 percent of the waking day, 28 hours a week, 1,460 hours (60.8 days) a year, and over 50 years about 12.5 years of waking days.
Good to know
Your habits will change over decades, so the long figures are an illustration of arithmetic, not a forecast. This tool does not judge whether the time is well spent.
Frequently asked questions
How is the share of the waking day worked out?
Screen hours ÷ waking hours × 100. Four hours on screens in a 16-hour waking day is 25 percent.
What are the two kinds of years?
Years left = lifespan − age. Years of waking days is hours × years left ÷ waking hours, so it counts only your awake time. Years of non-stop days is hours × years left ÷ 24, the same time laid end to end around the clock. Four hours a day over 50 years is 12.5 waking years or 8.3 non-stop years.
Does this say how much screen time is healthy?
No. It only turns your own numbers into hours, shares and years. It gives no health advice, and the lifespan is an assumption you choose, not a prediction.
Do screens used for work count?
That is up to you. Enter the total you want to measure, such as all screens or only leisure use. Many phones and computers show a daily average in their settings.