Computer & Electronics Calculators

Free online calculators and converters for electronics engineering, RF power calculations, number systems, and data storage units.

RF Power Calculators

Convert between watts, milliwatts, dBm (decibel-milliwatts), and dBW (decibel-watts) for RF engineering and telecommunications.

mW / W to dBm / dBW Calculator

Convert milliwatts or watts to decibel-milliwatts (dBm) or decibel-watts (dBW). Essential for RF signal power calculations.

  • Formula: P(dBm) = 10 · log₁₀(P(mW) / 1mW)
  • Instant conversion with step-by-step explanation

dBm / dBW to mW / W Calculator

Convert decibel-milliwatts (dBm) or decibel-watts (dBW) back to linear power units (mW or W).

  • Formula: P(mW) = 1mW · 10^(P(dBm)/10)
  • Useful for link budget calculations

mW to dBm Reference Table

Quick reference chart for common milliwatt to dBm conversions from 0.01 mW to 10 GW.

  • Complete conversion table
  • Formula explanation and examples

Electrical Calculators

Calculate voltage, current, power, and resistance using Ohm's Law and the power formula.

Volts, Amps, Watts & Ohms Calculator

Complete electrical calculator using Ohm's Law. Enter any two values to calculate the other two.

  • V = I × R (Ohm's Law)
  • P = V × I (Power formula)
  • Interactive power wheel diagram

Volts, Amps & Watts Calculator

Simple power calculator for electrical circuits. Calculate watts from volts and amps, or find missing values.

  • P = V × I
  • Quick and easy to use

Number System Converters

Convert between different number bases used in computing and digital electronics.

Binary, Octal, Hex & Decimal Converter

Convert numbers between binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16).

  • Essential for programming and digital electronics
  • Supports large numbers
  • Step-by-step conversion explanation

Data Storage Converter (Bits & Bytes)

Convert between bits, bytes, kilobytes, megabytes, gigabytes, terabytes, and more.

  • Binary (1024) and decimal (1000) standards
  • All common units: KB, MB, GB, TB, PB
  • Useful for storage and bandwidth calculations

Quick Reference

Common dBm to mW Conversions

dBm mW W
-30 dBm0.001 mW1 µW
-20 dBm0.01 mW10 µW
-10 dBm0.1 mW100 µW
0 dBm1 mW0.001 W
10 dBm10 mW0.01 W
20 dBm100 mW0.1 W
30 dBm1,000 mW1 W
40 dBm10,000 mW10 W

See complete mW to dBm table →

Frequently Asked Questions

What is dBm?

dBm (decibel-milliwatt) is a logarithmic unit of power referenced to 1 milliwatt. It's commonly used in RF engineering, telecommunications, and fiber optics to express signal power levels. The formula is: P(dBm) = 10 × log₁₀(P(mW)/1mW).

Why use logarithmic units like dBm?

Logarithmic units make it easier to work with the huge range of power levels in RF systems (from nanowatts to megawatts). They also simplify calculations: gains and losses can be added/subtracted instead of multiplied/divided.

What's the difference between dBm and dBW?

dBm is referenced to 1 milliwatt, while dBW is referenced to 1 watt. The relationship is simple: dBW = dBm - 30. So 0 dBm = -30 dBW = 1 mW, and 30 dBm = 0 dBW = 1 W.

What is Ohm's Law?

Ohm's Law describes the relationship between voltage (V), current (I), and resistance (R): V = I × R. Combined with the power formula P = V × I, you can calculate any electrical quantity if you know two others.