Axis

Sound level

decibeldB

Ten times the base-10 logarithm of a power ratio.

Dimension
1
Canonical signature
1
System
si accepted
Exactness
Exact

Definition record

How this unit is defined

Canonical base
This unit defines its own base.
Conversion type
log
Historical notes
Plain dB is a dimensionless power ratio; reference scales (dB SPL, dBV, dBm) are separate units.
Aliases
db, decibels

Same dimension

Related units

percentcommon%parts per millioncommonppmMach numbercommonMaparts per billioncommonppbspecific gravitycommonSGparts per trillioncommonpptexposure valuecommonEVper millecommon‰

Common conversions

Every conversion routes through the canonical base of the dimension.

This unit defines its own dimension.