Transmission ↔ OD ↔ dB calculator

Convert between transmission %, optical density and dB attenuation.

Category: Unit Converters

Formula: OD = -log₁₀(T) · dB = 10·OD

Inputs

InputParameterUnitDefault
TransmissionT%50

Result with the default inputs

  • Transmission: 50 %
  • Optical density: 0.301 OD
  • Attenuation: 3.0103 dB
  • Absorbance: 0.301

Open it with your own values: put each input in the address as a parameter, for example /calculators/transmission-od-db?T=50. A unit other than the listed one goes in <parameter>_unit.

Read more: Wikipedia: Absorbance

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