Never Use Your Laptop On Your Lap - Here's Why

Placing your laptop on your lap can lead to poor posture while you're sitting, but that's not the only reason why people don't recommend leaving it there for too long. Another reason is that you are blocking its ventilation. Your lap becomes a heat storage, which your body is not meant for, at least not for very high temperatures. In addition, blocking the ventilation can cause your device to overheat, requiring you to use a laptop cooling pad to continue using it. Ignoring these issues can actually harm your skin health and damage your laptop's internal components, a common consequence of common mistakes that could ruin your computer.

Some laptops have vents located underneath as a design choice to prevent debris from reaching the fans. Anything pressing against the bottom vents obstructs the airflow, which actually traps the heat back inside. Doing so could trigger thermal throttling, a mechanism that slows the CPU to prevent it from overworking when the system spikes to high temperatures. In some cases, the computer shuts down if the heat exceeds safe limits. None of these consequences is good for you, which is why people generally recommend placing laptops on hard, flat surfaces to provide maximum airflow while avoiding direct contact.

A study published in the Journal of Biomedical Physics and Engineering found that putting your laptop on your lap can cause issues with reproductive organs, like a decrease in sperm quality. Before you worry, this is not a common cause, but it can still happen. That's because most electronics, like laptops, emit small levels of low-frequency radiation, which is usually safe and similar to what you get when resting a Steam Deck or a Nintendo Switch on your lap. However, another study published in the Archives of Environmental & Occupational Health has suggested that moderate levels of electromagnetic fields could also disrupt fetal development if the laptop is "in close contact with a woman's womb," though using a laptop on your thighs is still fine. If you've already done this, it's not a big deal, as the radiation emitted is non-ionizing, meaning it shouldn't break molecular bonds or directly damage DNA because it's low energy.

Even though this radiation phenomenon is observed, safety checks are still in place to ensure they fall well below international safety guidelines. That means the emitted radiation won't ever hurt or kill you. In reality, electromagnetic fields are found in most home electronics, wireless devices, and even the electrical boxes near homes and offices. Their strength also depends on distance: the further away, the less exposure you have to it.

The dangers of a laptop overheating on your lap are easier to prove and far more dangerous than its radiation damage. Besides the experienced discomfort, too much heat produced by a laptop can have adverse effects on your skin. A laptop can burn your lap, especially if it's in contact with bare skin. Laptops can reach 52 degrees Celsius (125 degrees Fahrenheit), and sometimes even higher temperatures during internal heat transfer. That's too hot for humans to handle, as the burning threshold is around 44 degrees Celsius (111 degrees Fahrenheit). Thus, anything going above that means your skin gets burned. Repeated exposures can cause the Toasted Skin Syndrome (erythema ab igne), according to Healthline. This syndrome causes your skin to become discolored with a red-brown blotchy rash. It's harmless, but in very rare cases, it has links to skin cancer if it goes untreated.