Power conversion

dBm to Milliwatts conversion

Convert dBm to milliwatts (mW). Formula: mW = 10^(dBm/10). Free online tool — no sign-up. Clear formulas and worked examples. Runs locally in your browser.

Instant result

Result

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Enter values to convert.

Inputs —

Mode —

Formula —

Formulas

Core equations used by this converter.

FormulaP(mW) = 10^(dBm / 10)

iFollow the formulas shown. Calculation runs locally in your browser.

How to use

Take the level in dBm.

Divide by 10, then raise 10 to that power.

Result is milliwatts.

Example conversions

Common values with formula and result.

0 dBm to mW

10^(0/10) = 1 mW

1 mW

10 dBm to mW

10^(10/10) = 10 mW

10 mW

20 dBm to mW

10^(20/10) = 100 mW

100 mW

30 dBm to mW

10^(30/10) = 1000 mW = 1 W

1 W

dBm to Milliwatts conversion specification

Version 1.1.0 · Engine tested

Calculation status

Engine tested 4 published cases
Named expert review Not performed
Calculation version 1.1.0

Review policy

Definition: **Milliwatt (mW)** — 0.001 W; linear RF/electronics power. **dBm** — decibels relative to **1 mW**. Logarithmic: every +10 dB is ×10 power; +3 dB ≈ ×2.
What it calculates: Convert dBm to milliwatts (mW). Formula: mW = 10^(dBm/10). 0 dBm = 1 mW. Worked examples and chart.
Inputs: Values required by the selected conversion mode
Outputs: Converted result in the target unit or format
Formula: P(mW) = 10^(dBm / 10)
dBm to milliwatts conversion table: dBm Milliwatts (mW)
−30 0.001
−20 0.01
−10 0.1
0 1
3 ≈2
10 10
13 ≈20
20 100
30 1,000
40 10,000
Assumptions: Conversion runs locally in the browser; values are not uploaded.
Uses the formulas documented on this page.
Units: Formula
Boundary conditions: Empty or invalid input yields no valid result.
Out-of-range values may be rejected by the tool runtime.
Example: 0 dBm to mW → 1 mW
Validation cases: 0 dBm to mW → 1 mW
10 dBm to mW → 10 mW
20 dBm to mW → 100 mW
30 dBm to mW → 1 W
Sources: CalculatorX converter runtime
Standard unit / encoding definitions where applicable
Calculation version: 1.1.0

dBm	Milliwatts (mW)
−30	0.001
−20	0.01
−10	0.1
0	1
3	≈2
10	10
13	≈20
20	100
30	1,000
40	10,000

Background

Interpretation and common distinctions.

Use the converter tabs to switch direction when available. Results for dBm to Milliwatts conversion update locally in your browser.

Frequently asked questions

Key distinctions behind the conversion.

How do you convert using dBm to Milliwatts conversion?

Use P(mW) = 10^(dBm / 10). Example: 0 dBm to mW → 1 mW.

Can I switch direction?

Open the related reverse converter listed under Related tools.

Does this run online or locally?

Calculation runs locally in your browser. Values are not uploaded.

How precise are the results?

Results follow the formulas on this page. Round to the precision your use case needs.