How the Screen Time Tracker works

Screen time is easy to underestimate because it’s fragmented: 8 minutes here, 20 minutes there, “just one more” video, a couple of quick emails, and suddenly the day is gone. This calculator helps you turn scattered usage into a single number you can measure and improve.

You enter your typical hours per day on each device (phone, computer, tablet, TV/console). If you often use two screens at once (for example: TV while scrolling), you can use the overlap percentage to reduce double-counting. Finally, you choose how many days per week this pattern happens. The tool outputs daily, weekly, monthly, and yearly totals — plus a simple “how heavy is it?” meter for quick interpretation.

Formula breakdown (with overlap)

The core idea is simple: total time equals the sum of device times, minus estimated overlap. Overlap is modeled as a percentage of your total “raw” screen time. This is not perfect (real overlap varies), but it’s a practical correction that matches how people actually multitask.

• Raw daily screen time: raw = phone + computer + tablet + TV
• Overlap adjustment: overlapHours = raw × (overlapPct ÷ 100)
• Adjusted daily screen time: daily = max(0, raw − overlapHours)
• Weekly: weekly = daily × daysPerWeek
• Monthly (average): monthly = weekly × (52 ÷ 12) ≈ weekly × 4.333
• Yearly: yearly = weekly × 52

The calculator also estimates your waking hours using sleep: wakingHours = 24 − sleepHours. Then it shows what share of waking time is on screens: wakingShare = (daily ÷ wakingHours) × 100%. If you skip sleepHours, it assumes a typical 8 hours.

Examples

Example 1: “I’m on screens a normal amount… right?”

Phone 3.5h, computer 6h, tablet 0.5h, TV 2h. Raw = 12h/day. If you estimate 15% overlap (TV + phone, occasional multitasking), overlap = 12 × 0.15 = 1.8h. Adjusted daily = 10.2h. If this happens 5 days/week, weekly = 51h. That’s ~221 hours/month and 2,652 hours/year.

Put differently: 2,652 hours is about 110 full days — or almost 4 months of 24/7 time. Seeing it as “months” is often the first moment people take screen time seriously.

Example 2: The “one hour/day” cut

Suppose your adjusted daily screen time is 6.0h/day. Cutting just 1.0h/day for 30 days saves 30 hours. That’s enough time to finish a course, read 3–5 books, or build a meaningful side project. This is why small daily changes compound — the same way money compounds.

Example 3: Opportunity cost (optional)

Let’s say your yearly screen time is 1,500 hours and you value your time at $25/hour. The “opportunity cost” is 1,500 × 25 = $37,500. This is not saying screen time is “bad” — it’s simply a mirror. If you want to trade some of those hours for something else, the number helps you decide how much it’s worth.

Interpreting your results (a practical scale)

Screen time is context-dependent: a designer on a computer all day may have high screen time that’s productive, while someone doomscrolling may have lower total hours but worse outcomes. Still, a simple range helps you spot extremes quickly:

• 0–2 hours/day: Light. Often intentional usage or strict limits.
• 3–5 hours/day: Moderate. Common for many adults outside work.
• 6–8 hours/day: Heavy. Usually includes significant entertainment or multitasking.
• 9+ hours/day: Very heavy. Often indicates constant checking or multi-device habits.

The meter in this calculator caps at 12 hours/day for visualization. If you’re above that, the bar will show full — and your “yearly total” is the number to focus on.

FAQs

• Is this the same as my iPhone/Android “Screen Time” report? No. This is a fast estimator that lets you combine multiple devices and project weekly/monthly/yearly totals. Built-in reports are great, but they’re often device-specific. This tool is cross-device by design.
• What should I put for overlap? If you rarely multitask with screens, use 0–5%. If you often watch TV while scrolling, try 10–25%. If you constantly use two screens at once (common in gaming + phone), you might use 25–40%.
• Why is monthly calculated as weekly × 4.333? Months aren’t all the same length. Using 52 weeks per year divided by 12 months gives an average month length: 52/12 ≈ 4.333. It’s a clean projection for planning.
• Does “opportunity cost” mean screen time is wasted? Not at all. Screen time can be work, learning, or connection. The cost figure is optional — it’s just a way to price your attention if you’re planning a change.
• How do I reduce screen time without feeling miserable? Start with friction, not willpower: move distracting apps off your home screen, disable non-essential notifications, set “no-phone zones” (bed, meals), and replace one screen habit with a specific alternative (walk, book, stretch, journal). Track weekly totals so you see progress.
• Can I save multiple results? Yes — the “Save Result” button stores results locally in your browser (on this device). It’s private and never sent anywhere.

Disclaimer: This calculator provides estimates only. Actual screen time can vary by day and is best measured with device-level reports when precision matters.