How the calculation works
The calculation is a link budget. What the radio sends, minus the loss in the body and hand at both ends, has to arrive above the weakest signal the other radio can still hear. The distance at which the path uses up that budget is the range.3
Radios. PMR446 at its legal limit of 0.5 W e.r.p., with the receiver value European regulators use for planning, −111 dBm.12 Licensed UHF and VHF handhelds at 4–5 W or 1 W, with −117.4 dBm from Motorola, Hytera and Kenwood datasheets.101112
Paths. Open field: the ITU two-slope model for two antennas at 1.5 m, up to the 10.1 km radio horizon.37 Suburb, town center and between buildings: the ITU street-level model built on measurements in two UK cities.3 Inside a building: the ITU indoor model plus each wall and floor you add.45 One radio inside: the ITU building entry loss.6 At VHF, electrical noise in towns raises the weakest usable signal.8 A built-up area never gets more range than open ground; where the VHF estimate says otherwise, we show the open-ground figure.
Two figures. Signal changes from spot to spot, so the answer is a span: the first figure works at 9 in 10 spots, the second at half of them.
PoC radios have no range between the radios: the call goes over the mobile network. The check compares the signal outside, by the usual signal classes,15 minus the building entry loss, with about −105 dBm that a radio needs.6 In a 2024 study of three buildings in Bonn, none had reception in the basement.14
Estimates. Some inputs have no published value at these frequencies: wall and floor losses below 900 MHz, the body loss of 9 dB and the VHF correction in towns. The expert view shows every number.
What others say
| Who | PMR446 range they give |
|---|---|
| ECC Report 369 (CEPT), planning calculation | 0.58 km in a town, 1.0 km in a suburb, 3.2 km in the countryside, without body loss or a margin1 |
| ECC Report 369, simulation for 95 % of links | 90–100 m in a town, 100–130 m in a suburb, 0.7–1.0 km in the countryside1 |
| Elektroniskie sakari, Latvia's spectrum office | A few hundred meters in a city, up to a few kilometers in the countryside13 |
| Motorola XT400 datasheet (maker's claim) | Up to 9 km line of sight; coverage varies with terrain and conditions9 |
| This calculator, 9 in 10 spots – half of the spots | 370–620 m in a town center, 550–920 m in a suburb, 770 m–1.3 km in open field |
Questions
How far does a PMR446 walkie-talkie reach?
About 370–620 m in a town center, 550–920 m in a suburb and 770 m–1.3 km in open field, by ITU-R propagation models at the 0.5 W legal limit. Latvia's spectrum office puts it at a few hundred meters in a city and up to a few kilometers in the countryside.
Why does the box say up to 9 km?
Makers quote line of sight in ideal conditions. Motorola gives up to 9 km for its XT400 and adds that coverage varies with terrain and conditions. Two radios at head height on flat ground cannot see past about 10.1 km, because the Earth curves away between them.
How much signal do walls and floors take?
At 446 MHz a 20 cm concrete wall takes about 8 dB, reinforced concrete about 15 dB and metal 30 dB or more. One concrete floor takes 9 dB, two take 19 dB. Every 6 dB halves the distance.
Does a PoC radio have a range limit?
Not between the radios: the call goes over the mobile network, so each radio only needs signal where it is. A typical building takes about 14.2 dB of that signal, an energy-efficient one with coated windows about 31.3 dB. Basements often have none.