Reading
National Center for Education Statistics (2022) β Reading time survey; Orben & Przybylski (2019) β Meta-analysis of screen time displacement, 30% default
Non-phone kids read ~22 min/day (NCES 2022)
Current projection: 161 hrs
See what waiting protects
Your child asks for a phone. Before you decide, see exactly how many hours of reading, sleep, and free play you preserve by waiting β with research you can check.
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Check the math
Every number above comes from a cited study. Tap any panel to see the source, adjust the assumption, and watch the projection update live.
Sleep
CDC (2024) β Sleep guidelines by age; Twenge et al. (2018) β Screen time & sleep displacement, n=40,000+, 25% default coefficient
CDC sleep guideline gap for age (e.g., ~1 hr/night at age 10)
Current projection: 365 hrs
Outdoor Play
Hofferth & Sandberg (2001) PSID Child Time Diaries β 90 min/day baseline; AAP (2019) β Unstructured play displacement, 20% default
Kids spend ~90 min/day in unstructured outdoor play (Hofferth 2001)
Current projection: 438 hrs
Your decision anchor
Save this scenario for your partner, share a link, print for the fridge, or add another child β all without an account.
Sources & methodology
Reading: NCES 2022 & Orben & Przybylski 2019
Baseline: 22 min/day recreational reading for children without phones (NCES 2022). Displacement: 30% default from Orben & Przybylski (2019) meta-analysis of 355 effect sizes β each hour of screen time associates with ~0.3 hrs less reading. Adjustable 15β45%.
Sleep: CDC 2024 Guidelines & Twenge 2018
Baseline: Age-specific gap between CDC recommended sleep and typical sleep (e.g., ~60 min/night at age 10). Coefficient: 25% default from Twenge et al. (2018), n=40,000+ adolescents β each hour of screen time associates with ~15 min less sleep. Adjustable 10β40%.
Outdoor Play: Hofferth 2001 & AAP 2019
Baseline: 90 min/day unstructured outdoor play from Hofferth & Sandberg (2001) PSID time diaries (n=3,500+ children). Displacement: 20% default from AAP (2019) policy on media displacement of play. Adjustable 10β35%.
How is "years of delay" calculated?
Simple difference: proposed phone age minus current age. A 10-year-old waiting until 14 = 4 years of delay. Each year compounds daily hours Γ 365.
Can I trust these numbers?
These are projections based on population-level research averages, not guarantees for your specific child. The value is making the trade-off visible and adjustable. All sources linked β you decide what assumptions fit your family.