dBm to Milliwatts / Watts converter (dBm to mW / W)
Convert dBm (dBm) to Milliwatts / Watts (mW / W) with this free calculator. Type a value, press Convert, and the page applies the same factor shown in the formula below — no rounded shortcut, and nothing is stored on a server.
How to convert dBm to Milliwatts / Watts
dBm is a logarithmic unit of power relative to 1 milliwatt.
P(mW) = 10^(dBm/10) | P(W) = 10^(dBm/10) ÷ 1000
Use the formula:
Example: Convert 10 dBm:
P(mW) = 10^(10÷10) = 10 mW, P(W) = 0.01 W
What is a dBm?
The dBm (dBm) is the starting or target unit on this page. Use the calculator above to convert values without looking up the factor by hand.
What is a Milliwatts / Watts?
The Milliwatts / Watts (mW / W) is the starting or target unit on this page. Use the calculator above to convert values without looking up the factor by hand.
This page converts power from dBm into Milliwatts / Watts. Use the formula above for the exact relationship between the two units.
How this calculator works
The form on this page is a dBm-to-Milliwatts / Watts converter. After you enter a number, JavaScript multiplies or rearranges it with the published conversion factor and writes the mW / W result in the output box. The step-by-step panel repeats the arithmetic so you can copy it into homework or a spreadsheet.
Reviewed by Hamsen, founder of GigaTables and a biology engineer. See the about page for how formulas are checked before a tool is published.
FAQ
How many mW / W are in 1 dBm?
Use the formula in the section above. Temperature and logarithmic units are not a single multiply-by-a-constant step.
How do I convert dBm to Milliwatts / Watts?
Use the formula:
Is this dBm to mW / W converter free?
Yes. GigaTables calculators are free to use in a browser. You do not need an account, and the values you type are not uploaded.