What is SAR? Understanding Mobile Phone Radiation & Legal Limits

Every Phone Emits Energy: The Basics of SAR

Every time you make a call, send a text, or browse the internet, your smartphone connects to a mobile network. To do this, it emits a small amount of radiofrequency (RF) energy. While modern devices are designed and tested to be safe, understanding exactly how much of this energy your body absorbs is a crucial part of using technology responsibly.

This measurement is known as the Specific Absorption Rate, commonly referred to as SAR.

Most users never see this data when buying a new phone, yet it’s one of the most important indicators of safe and responsible phone use. At SarList.org, our goal is to bring this information to the forefront.

What Does SAR Actually Measure?

In simple terms, SAR measures the rate at which human tissue absorbs RF energy from a mobile device or any wireless equipment. It is expressed in watts per kilogram (W/kg).

When you hold a phone to your ear or keep it in your pocket, your body absorbs a portion of the electromagnetic energy the device is transmitting. The SAR value tells you the maximum amount of radiation absorbed by your head or body under controlled, worst-case testing conditions (such as when the phone is transmitting at its highest certified power level).

A lower SAR value generally means that the device emits less RF energy into the user’s body compared to a device with a higher value. However, it is important to remember that as long as a phone is below the legal limit, it is considered safe for everyday use.

“Head” vs. “Body” SAR: What is the Difference?

When you check a device on the SarList database, you will usually see two different SAR values:

• Head SAR: This value is measured with the phone placed directly against the ear, simulating a standard voice call. It is a critical metric for those who frequently make long phone calls without using a headset or speakerphone.
• Body SAR: This value is measured with the phone placed at a specific distance (usually 5mm to 15mm) from the torso. This simulates carrying the phone in a pocket, held in your hand, or clipped to your belt.

Some manufacturers also provide a “Simultaneous” SAR value, which measures the combined radiation output when multiple antennas (Cellular, Wi-Fi, and Bluetooth) are transmitting at the same time.

Global Standards: EU vs. FCC Limits

To ensure consumer safety, regulatory bodies around the world have established strict legal limits for SAR. Phones that exceed these values cannot be legally sold in their respective markets. However, the testing methods and limits differ significantly between Europe and the United States:

• European Union (EU): The limit is capped at 2.0 W/kg, averaged over 10 grams of tissue. This standard is generally adopted by most European countries and several other regions globally.
• United States (FCC): The Federal Communications Commission enforces a stricter limit of 1.6 W/kg, averaged over 1 gram of tissue.

Because the measurement methods (10g vs. 1g of tissue) are different, you cannot directly compare an EU SAR value with a US SAR value. This is why our database clearly separates the data based on the region.

Why You Should Care About SAR Values

Even though all modern phones meet these legal limits, the actual SAR values can vary drastically between different models and brands. For example, one flagship smartphone might have a Head SAR of 0.40 W/kg, while another might push close to the 1.6 W/kg limit.

Knowing your phone’s SAR level provides transparency and allows you to make informed decisions. If you are concerned about RF exposure—perhaps you use your phone for hours a day or are buying a device for a child—checking the SAR value before purchasing adds an extra layer of awareness.

Safety begins with knowing your phone and understanding your exposure.

Ready to find out how your phone ranks? Visit our Search Page to instantly check and compare the SAR levels of thousands of smartphones sold in Europe and the United States.