WiFi router RF exposure
Last reviewed: 19 October 2026
A Wi-Fi router is a low-power radio transmitter that stays on all day, usually a few metres from where people sit or sleep. This page collects the transmit-power caps routers ship under, the limits that apply at Wi-Fi frequencies, and what the dated sources conclude — without going beyond them.
Typical levels and limits, with dated sources
- Routers transmit in the 2.4 GHz and 5 GHz bands (Wi-Fi 6E adds 6 GHz) at power levels capped by regulators. In the EU, 2.4 GHz WLAN equipment is limited to 100 mW EIRP (ETSI EN 300 328); US rules allow up to 1 watt for 2.4 GHz spread-spectrum and digitally modulated systems (47 CFR § 15.247), and higher sub-band limits apply at 5 GHz.
- The ICNIRP general-public reference level above 2 GHz — covering both Wi-Fi bands — is 10 W/m², far above the power density produced by a router at the distances people actually live at (ICNIRP, 2020).
- The WHO states that, considering the very low exposure levels and the research collected to date, there is no convincing scientific evidence that the weak RF signals from base stations and wireless networks cause adverse health effects (WHO, "Electromagnetic fields and public health: base stations and wireless technologies", Fact sheet No. 304, 2006).
- IARC classified radiofrequency electromagnetic fields — the kind all Wi-Fi equipment uses — as "possibly carcinogenic" (Group 2B) in 2011, based on limited evidence (Baan et al., Lancet Oncology 12(7): 624–626, 2011; IARC Monographs Vol. 102).
How distance and walls change exposure
- RF power density falls with the square of distance from the antennas: doubling your distance from the router leaves roughly a quarter of it. Moving a router from the desk next to you to another room is the single biggest lever.
- Walls weaken a Wi-Fi signal (that is why coverage drops across a home), and the same attenuation applies to the exposure where you sit — a signal too weak to reach the next room is also one whose field has fallen off along the way.
- Wi-Fi traffic is bursty and shared among devices: the radio is not transmitting at full power continuously, so time-averaged exposure is lower than peak ratings suggest.
Try it in the calculator
This link opens the calculator with the Tablet emitter pre-selected — tablets use the same 2.4/5 GHz Wi-Fi bands as the router — and lets you set the distance you sit from it to see the modelled estimate next to the ICNIRP public reference level.
Sources
- ICNIRP (2020), "Guidelines for limiting exposure to electromagnetic fields (100 kHz to 300 GHz)", Health Physics 118(5): 483–524.
- ETSI EN 300 328, "Wideband transmission systems; Data transmission equipment operating in the 2,4 GHz band; Harmonised standard for access to radio spectrum" (100 mW EIRP limit for 2.4 GHz WLAN).
- FCC (1997), "Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields", OET Bulletin 65; 47 CFR § 15.247 (2.4 GHz power limits).
- WHO (2006), "Electromagnetic fields and public health: base stations and wireless technologies", Fact sheet No. 304, May 2006.
- Baan et al., IARC Working Group (2011), "Carcinogenicity of radiofrequency electromagnetic fields", The Lancet Oncology 12(7): 624–626; IARC Monographs Vol. 102.
Educational information, not medical advice. Numbers above are limits and findings as stated by their dated sources; our calculator's output is a model-based estimate, not a measurement. No adverse health effects are confirmed below international limits, and research on long-term effects is ongoing — see About for our editorial position.