Decibel to Linear Calculator

About this calculator

Decibels express a ratio on a logarithmic scale, which compresses huge real-world ranges — like the difference between a whisper and a jet engine — into manageable numbers, but that also means dB values can't simply be added or divided the way linear quantities can. Converting back requires knowing whether the dB value represents a power ratio (10^(dB/10), used for quantities like power, energy, or intensity) or a field/amplitude ratio (10^(dB/20), used for quantities like voltage, current, or sound pressure) — the factor-of-two difference in the exponent trips up beginners constantly.

This calculator takes a decibel value and your choice of power or field basis and returns the equivalent linear ratio. Audio engineers setting gain staging, RF and telecom engineers computing link budgets, and electronics students converting amplifier or antenna specs use it to move between the dB figures on a datasheet and the actual multiplicative ratio they represent.