dBm to dBW Conversion
dBW = dBm − 30
Quick answer
This calculator solves dBW = dBm − 30 for Power (dBW). With Power (dBm) 44 dB, the result is 14 dB. It solves in 2 directions, so you can enter the values you have and get the one you need.
Calculator
Formula
Description
dBm references power to 1 milliwatt, while dBW references power to 1 watt. Since 1 W = 1000 mW, the difference is exactly 30 dB. This conversion is trivial but essential when working with RF link budgets where some parameters are specified in dBm and others in dBW. Satellite communications typically use dBW (or dBW/m² for flux density), while terrestrial RF and cellular systems predominantly use dBm. A 0 dBm signal is 1 mW = −30 dBW, and a 0 dBW signal is 1 W = +30 dBm.
Variables
- dBW — Power in decibels relative to 1 watt
- dBm — Power in decibels relative to 1 milliwatt
Practical Notes
Common reference levels: 0 dBm = 1 mW = −30 dBW, 30 dBm = 1 W = 0 dBW, 40 dBm = 10 W = 10 dBW. Wi-Fi access points typically transmit at 20-23 dBm (100-200 mW). Cellular base stations transmit at 43-46 dBm (20-40 W). Satellite uplinks can be 50-60 dBW (100 kW − 1 MW EIRP).
Symbols and units
| Symbol | Meaning | Default unit | Accepted units |
|---|---|---|---|
| dBW | Power (dBW) | dB | dB |
| dBm | Power (dBm) | dB | dB |
Step by step
- 1. What you know: Power (dBm) 44 dB
- 2. The relation: dBW = dBm − 30
- 3. Substitute: dBm = 44 dB
- 4. Result: Power (dBW) = 14 dB
Worked examples
Minimum range
Given: Power (dBm) 0.66 dB
Result: Power (dBW) = -29.34 dB
Low range
Given: Power (dBm) 6.6 dB
Result: Power (dBW) = -23.4 dB
Typical
Given: Power (dBm) 44 dB
Result: Power (dBW) = 14 dB
High range
Given: Power (dBm) 132 dB
Result: Power (dBW) = 102 dB
Maximum range
Given: Power (dBm) 1320 dB
Result: Power (dBW) = 1290 dB
Solving for each variable
Solve for Power (dBW)
Power (dBm) 0.66 dB → -29.34 dB
Solve for Power (dBm)
Power (dBW) 0.3 dB → 30.3 dB
How Power (dBW) changes with Power (dBm)
| Power (dBm) (input) | Power (dBW) (result) |
|---|---|
| 9.68 dB | -20.32 dB |
| 24.2 dB | -5.8 dB |
| 48.4 dB | 18.4 dB |
| 72.6 dB | 42.6 dB |
| 96.8 dB | 66.8 dB |
| 145.2 dB | 115.2 dB |
| 193.6 dB | 163.6 dB |
| 387.2 dB | 357.2 dB |
| 677.6 dB | 647.6 dB |
| 968 dB | 938 dB |
Embed this calculator
Paste this into any page. It keeps working when this page updates, and credits the source.
<iframe src="https://vbatpower.com/embed/dbm-dbw/" width="100%" height="460" style="border:1px solid #1f2a37;border-radius:12px" loading="lazy" title="dBm to dBW Conversion"></iframe>
<p><a href="https://vbatpower.com/formulas/dbm-dbw/">dBm to dBW Conversion</a> Calculator by vbatpower.com</p>Frequently asked questions
How do you calculate dBm to dBW Conversion?
Use dBW = dBm − 30. With Power (dBm) 44 dB, Power (dBW) works out to 14 dB.
What is the formula for dBm to dBW Conversion?
The formula is dBW = dBm − 30. dBm references power to 1 milliwatt, while dBW references power to 1 watt.
How do you find Power (dBm) when you know the other values?
Rearrange for Power (dBm): with Power (dBW) 0.3 dB, Power (dBm) is 30.3 dB.
Related Concepts
All Signal & dB formulas →Need more features?
Save calculations, import telemetry data, simulate battery discharge, and collaborate with your team.
Try the App