dBm

Units & Measurements abbreviation · Engineering Unit

dBm
Stands forDecibel-milliwatts
CategoriesUnits & Measurements

dBm stands for Decibel-milliwatts, an engineering unit abbreviation.

Power level in decibels relative to one milliwatt, used for radio transmitters, Wi-Fi and cellular signal strength, and fiber-optic links. 0 dBm equals 1 mW, 20 dBm equals 100 mW and 30 dBm equals 1 W.

Example: Signal strength: −67 dBm, good enough for reliable video calls.

Usage notes

Received signals are tiny, so readings are negative: Wi-Fi stronger than about −67 dBm is considered good, and below about −80 dBm connections become unreliable. Each 3 dB step doubles or halves the power. Phones in field-test mode display cellular signal in dBm rather than bars.

More engineering unit abbreviations

  • cfm – Cubic feet per minute
  • Ci – Curie
  • CID – Cubic inch displacement
  • CRI – Color Rendering Index
  • dB – Decibel
  • dBA – A-weighted decibels
  • F – Degree Fahrenheit
  • fc – Foot-candle
  • fpm – Feet per minute
  • fps – Feet per second
  • ft-lb – Foot-pound
  • g – Standard gravity (g-force)

See all 103 engineering unit abbreviations →

Edited by the AbbreviationList.com team. Spotted an error or a missing meaning? Contact us.