Convert logarithmic dBm power to watts and milliwatts.
✓ Reviewed July 26, 2026◇ Runs locally○ No sign-up
Global formulaFormula-based estimate
=Your result will appear here
Enter values and calculate.
APPLICABILITY
Where this result fits
Region
Global formula
Result type
Formula-based estimate
Standards basis
NIST Guide to the SI
Edition / version
Named formula or standard edition; implementation reviewed July 26, 2026
Important: Confirm equipment ratings, installation conditions, protection requirements, and the electrical code adopted where the work will be performed. Electrical safety policy →
STEP BY STEP
How to use the dBm to Watts Converter
Enter the known electrical values and choose the applicable phase where offered.
Select Calculate to apply the formula shown on this page.
Review units and assumptions before using the result in design work.
Have safety-critical work checked against equipment instructions and local electrical code.
ACCURACY & LIMITS
What to know before using the result
dBm is an absolute power unit referenced to 1 mW.
Do not confuse dBm with dB gain or loss.
HELP
Frequently asked questions
How accurate is the dBm to Watts Converter?
The calculator uses the formula shown on this page and keeps full numeric precision internally before formatting the result. dBm is an absolute power unit referenced to 1 mW.
Does the dBm to Watts Converter upload my input?
No. The calculation or processing runs locally in your browser. UtiliNest does not receive or store the values you enter.
Can I use the dBm to Watts Converter on a phone?
Yes. The inputs, result controls, and explanatory content are designed for current mobile and desktop browsers.
Where does the dBm to Watts Converter apply?
Applicability: Global formula. Result classification: Formula-based estimate. Confirm equipment ratings, installation conditions, protection requirements, and the electrical code adopted where the work will be performed.
SOURCES
Definitions and references
Reviewed against the references below on July 26, 2026. Links open the source publisher's website. Read the source policy →