Decibel to Watt Converter | dBW & dBm

🔊 Decibel to Watt Converter

Convert dBW and dBm to watts and milliwatts for smart home audio, WiFi, Zigbee, Z-Wave, and RF IoT devices.

Presets

Converter

Conversion Mode

Reference Context

Input Value (dBW)

📊 Conversion Results

Smart Home Device Reference (dBm / dBW)

20 dBmWiFi Router TX

0 dBmZigbee Device

4 dBmBluetooth 4/5

14 dBmZ-Wave Plus

0 dBW1 W Amplifier

10 dBW10 W Speaker

20 dBW100 W Receiver

-30 dBmSatellite RX

dBW / dBm Conversion Table

dBW	dBm	Watts	Milliwatts	Example Device
-30 dBW	0 dBm	0.001 W	1 mW	Zigbee node
-20 dBW	10 dBm	0.01 W	10 mW	Z-Wave device
-10 dBW	20 dBm	0.1 W	100 mW	WiFi router
0 dBW	30 dBm	1 W	1,000 mW	Small amplifier
5 dBW	35 dBm	3.16 W	3,162 mW	Mini amp
10 dBW	40 dBm	10 W	10,000 mW	Smart speaker
20 dBW	50 dBm	100 W	100,000 mW	Subwoofer
30 dBW	60 dBm	1,000 W	1,000,000 mW	PA amplifier
40 dBW	70 dBm	10,000 W	10,000,000 mW	High-power PA
-60 dBW	-30 dBm	0.000001 W	0.001 mW	Satellite RX signal

Smart Home RF Protocol Power Table

Protocol	Typical TX Power (dBm)	Typical Range	Power (mW)
WiFi 2.4GHz (802.11n)	20 dBm	30–50 m indoor	100 mW
WiFi 5GHz (802.11ac)	17 dBm	15–30 m indoor	50 mW
Zigbee (802.15.4)	0–8 dBm	10–20 m indoor	1–6.3 mW
Z-Wave (700 series)	14 dBm	30–40 m indoor	~25 mW
Bluetooth 5.0 LE	4–10 dBm	10–40 m	2.5–10 mW
Thread / Matter	0–8 dBm	10–20 m indoor	1–6.3 mW
433 MHz RF Sensor	10 dBm	Up to 100 m	10 mW
EnOcean	3 dBm	10–30 m	~2 mW

IoT RF Power Tip: In smart home RF devices, every 3 dBm increase doubles transmitted power. A WiFi router at 20 dBm (100 mW) is 100x more powerful than a Zigbee node at 0 dBm (1 mW) — yet both can reliably cover a typical room thanks to mesh networking and frequency selection.

Smart Home Audio Tip: For audio amplifiers, perceived loudness roughly doubles every 10 dBW increase (or every 10x increase in watts). A 10 W smart speaker (10 dBW) sounds noticeably louder than a 1 W speaker (0 dBW), but you would need 100 W (20 dBW) to sound twice as loud as 10 W to the human ear.

A decibel-watt converter is a tool that changes power values between various units, for instance decibel-milliwatts (dBm), decibel-watts (dBW) and watts (W). In the world of RF energy, levels of power range greatly so such converters really help. They let you go from dBm to watts or vice versa, from watts to dBm. Some of them also handle dBW, megawatts and kilowatts.

What exactly does dBm mean? It shows a power level in decibels regarding one milliwatt (1 mW) as a base. Because of the wide scope of power values, optical and signal levels commonly appear on a logarithmic scale by means of dBm.

How to convert between dBm, dBW and watts

Decibels help to compare amounts that differ in orders of magnitude. For radio or audio signals the standard puts 1 milliwatt at 0 dBm.

To convert watts to dBm you use a formula. Power in dBm equals 10 times the logarithm (base 10) of power in watts plus 30. Those 30 decibels come from the fact taht 1 watt equals 1000 milliwatts, and the logarithm of 1000 is 30 dB.

So a dBW value in dBm is always higher by 30. For instance 10 dBm (10 milliwatts) equals -20 dBW (0.01 watts).

Going the other way, to go from dBm to watts, you multiply the result buy 10 to the negative third power, to pass from milliwatts to watts. Here is a practical example. If a wireless signal has 30 dBm, you calculate the watt value by means of those steps.

Power in watts equals 10 raised to (dBW divided by 10). That is how you convert from dBW back to watts.

Most of these converters are very easy to use. You enter power in dBm and click to convert. Or enter watts and click to convert.

Some work on computers, phones and tablets. You can convert watts to dBm and dBW, dBW to watts and dBm, or milliwatts to dBm and dBW. It simply depends on the starting unit.

An important fact is that decibels themselves do not have units. A decibel expresses a power ratio, and because of that it stays unitless. Such calculations for radio and signals become much more simple, whichexplains their wide usage in such tools.