July 7, 2025, 1:26 am | Read time: 6 minutes

Tablets in the kids’ room, watching series before bed, playing on smartphones during school breaks: For many families, this is already part of everyday life. But how much screen time is still acceptable for children and teenagers—and when does it become concerning? FITBOOK writer Doris Tromballa has gathered the most important numbers, recommendations, and tips.

How Much Screen Time Is Okay?

Of course, not all screen time is the same: Today, many children, for example, do their homework on screens. What worries Dr. Janna-Lina Kerth from the German Society for Pediatric and Adolescent Medicine (DGKJ) is: “When you walk through the city, you see children incredibly often who are still sitting in strollers and already have a cell phone in their hands.” Together with other medical societies, the DGKJ has developed guidelines with recommendations for leisure screen time for children and adolescents³:

• 0-3 years: Screen-free!
• 3-6 years: Maximum 30 minutes on individual days and with an adult!
• 6-9 years: No more than 30 to 45 minutes on individual days and with an adult!
• 9-12 years: No more than 60 minutes of recreational screen use!
• 12-19 years: No more than two hours of recreational screen use!
• 16-18 years: Guideline value – still no more than 2 hours of recreational use!

The DGKJ is even stricter than the World Health Organization (WHO), which, for example, only recommends absolute screen freedom up to the age of two.⁴ According to a recent OECD analysis, almost three-quarters of 15-year-olds spend more than two hours on a typical school day on TikTok, gaming, or other digital activities.⁵

Behavior Indicating Addiction

What Happens With Too Much Screen Time?

Dr. Janna-Lina Kerth, a pediatrician at the University Hospital Düsseldorf, understands parents who occasionally put their children in front of a screen. After all—as many parents know from experience—the child is almost immediately occupied or distracted. “But often you buy yourself time in the short term, which you pay for later,” she explains. Studies show, for example, that too much screen time shortens children’s sleep.⁶

Additionally, she explains that it is very important for development that children perceive, get to know, and understand their environment: “Time spent in front of the screen is no longer spent in other ways, such as outside with siblings, where children can then let off steam. This can lead to delayed motor development and higher body weight.”⁷ Nearsightedness is also closely linked to excessive screen time, “especially in early childhood when the eyeballs are still developing,” explains Dr. Janna-Lina Kerth. “This is generally true for books as well—but it’s not very likely that a very young child will have a book right in front of their nose for several hours every day. With a cell phone, that can certainly become an everyday occurrence.”

Too Much Screen Time Also Has Alarming Effects on the Brain

The extensive ABCD study by the National Institutes of Health (NIH) found that children who spent more than two hours a day on screen activities performed worse on language and thinking tests. In some children who spent more than seven hours a day on screens, the cortex, the area of the brain responsible for critical thinking and reasoning, was even thinned.⁸ Other studies have shown that excessive screen time leads to poorer academic performance and more behavioral problems in children.⁹

Phones Also Cause Problems in Social Life

The more screen time, the fewer friends, according to the ABCD study. It found that children who spent more time on screens had poorer academic performance and more behavioral problems.¹⁰ The study also showed that excessive screen time is associated with more behavioral issues in children.¹¹

However, there are also signs of problematic behavior that are not directly related to screen time but rather to behavior that indicates addiction. Pediatrician Dr. Janna-Lina Kerth points out: “It’s problematic, for example, when children or teenagers can’t stop at all: They get up secretly at night to get the phone from the living room or sit in front of the computer. Or when relationships start to suffer: There is less and less contact with friends or family. Or when everything else becomes unimportant: Hobbies are neglected, or school is neglected. These are things that indicate a loss of control.”

What Can Parents Do?

By the time children reach their teenage years, parents face the challenge of managing screen time. Kids and teenagers want to communicate, learn new things, and satisfy their curiosity—all of which phones and other devices offer.¹² Therefore, scientists recommend that parents avoid falling into the phone trap unprepared and engaging in a power struggle with their children. They advise: Make clear agreements that are binding for everyone. It may seem like a good idea at first, but it’s important to genuinely engage with what your kids are doing online.

However, try not to act like a “detective meticulously recording possible addictive behavior: Kids notice that pretty quickly and feel monitored—it’s important to build trust. It’s better to ask: ‘Can you tell me about the computer game you’re playing?’ or have them show you what they’re interested in,” explains Dr. Janna-Lina Kerth. It’s important to always keep the conversation going about what’s so fascinating on the screen. “And do that later too—not just while the kids are young, but always stay engaged.”

And one aspect should be particularly kept in mind, emphasizes Dr. Janna-Lina Kerth: the role model function of parents. Studies have shown that children become aware very early on of how much time parents spend on their phones and what they do there, and that the interruptions and associated mental and emotional absence make them feel sad. They sense when they are losing out to the screen.¹³ These parental screen habits do not go unnoticed by children: On one hand, they end up spending more time on their phones or in front of the computer themselves, and on the other hand, there are also bonding problems between parents and children, increased anxiety, more withdrawal, and poorer problem-solving skills.¹⁴

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Where to Find Help for Screen Problems?

Many teenagers are quite aware that cell phones and similar devices can also be problematic, says Dr. Janna-Lina Kerth. If there is a stable, trusting relationship between parents and children, it is easier for them to talk to their parents when they feel something might be wrong. “In my experience, most children are open to such conversations,” she encourages. She also points to online self-tests for media consumption, such as those from the Federal Institute for Public Health or the University of Heidelberg. Additionally, there is straightforward email counseling available from the Federal Institute for Public Health. Parenting counseling centers, pediatricians, and child and adolescent psychotherapists also offer help.