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Gain Calculator

Convert dB to linear multiplier or linear to dB (amplitude or power), and add up a chain of gain stages to find the total gain and output level — with a clipping check.

Gain in decibels is logarithmic, so stages add in dB but multiply as linear factors. +6 dB ≈ double the amplitude; +20 dB = ten times. This is a calculator, not a measurement.

Decibels ↔ linear multiplier

Amplitude (voltage): dB = 20·log₁₀(factor). Power: dB = 10·log₁₀(factor). Edit either field.

Common dB ↔ amplitude factors

Amplitude (voltage) multipliers — power factors are the square of these.

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How Gain in dB Works

Gain is the factor by which a signal is multiplied — this dB multiplier tells you how many times larger or smaller the output is relative to the input. Expressed in decibels it’s logarithmic: for amplitude (voltage gain), dB = 20·log₁₀(factor), and the factor is 10^(dB/20). For power it’s 10·log₁₀(factor) and 10^(dB/10), because power scales with amplitude squared. So +6 dB roughly doubles amplitude (×1.995), +20 dB is ×10, and −6 dB halves it.

Because decibels are logarithmic, cascaded gain stages add in dB while their linear factors multiply. A +12 dB preamp, a −3 dB pad and a +6 dB stage total +15 dB — and applied to a −18 dBFS input give −3 dBFS out. Watching that running total is the essence of gain staging: keep levels healthy without pushing the output past 0 dBFS, where digital clipping occurs.

The distinction between amplitude gain and power gain matters when you cross domains. Voltage gain — the ratio of output to input voltage — uses the 20·log formula and covers microphone levels, audio interfaces, and op-amp circuits; power ratios (RF amplifiers, antenna systems, acoustic watts) use 10·log. The same physical ratio — say, a tripling of the value — is +9.5 dB in amplitude but only +4.8 dB in power. This calculator lets you switch between the two so the right formula is always applied. For audio work, amplitude (voltage) is almost always what you want; power gain is more relevant to speakers, transmitters, and acoustic measurements you'd cross-check with a sound pressure level calculator.

In a typical DAW recording chain, practical gain staging means: set the mic preamp so peaks land around −18 dBFS (leaving 18 dB of headroom), track into plug-ins that like −18 dBFS nominal, then trim the master bus so the final mix peaks no higher than −1 dBFS before mastering. You can model each stage here — preamp gain, channel fader, plug-in trim — by entering them as comma-separated dB values to verify the chain doesn’t clip before you commit to recording. To verify how loudness targets fit this picture, pair this tool with the loudness normalization tool to find the exact gain adjustment needed to reach a target LUFS.

Frequently Asked Questions

How many dB is double the volume?
Double the amplitude is +6 dB (×2). Double the power is +3 dB. Perceived "twice as loud" is roughly +10 dB — loudness perception is a separate thing from the raw factor.
Why 20·log for amplitude but 10·log for power?
Power is proportional to amplitude squared, and 10·log₁₀(factor²) = 20·log₁₀(factor). So a given ratio yields the same dB whether you compute it from amplitude (×20) or power (×10).
Do gain stages add or multiply?
In decibels they add; as linear factors they multiply. +6 dB then +6 dB is +12 dB total, which is ×2 then ×2 = ×4 in amplitude.
What is good gain staging?
Setting each stage so the signal is strong relative to noise but never reaches 0 dBFS (digital clipping). This calculator’s staging mode sums your stages and flags if the output would exceed 0 dBFS.
Is a negative gain the same as attenuation?
Yes. A negative dB gain is a cut: −6 dB is a linear factor of about 0.5 (half the amplitude). Enter negatives in the staging list for pads and faders pulled down.
Does this change my audio?
No. It only computes the math from the numbers you enter. Apply the gain in your mixer, DAW or device.
What does 0 dBFS mean, and why does my output clip there?
0 dBFS (decibels relative to full scale) is the maximum representable digital level — the point where every bit in the audio word is set to 1. Any signal that exceeds 0 dBFS wraps or hard-clips, producing harsh distortion. The staging calculator flags this: if your input level plus the sum of your stage gains exceeds 0 dBFS, the output is shown in red. Aim for peaks at −1 to −3 dBFS to leave a small safety margin, especially before mastering limiters.
How do I calculate the total gain through a preamp and mixer chain?
Enter your input level in dBFS (or dBu/dBV if you convert first), then list each stage's gain in dB separated by commas — for example a +24 dB preamp, a −6 dB pad, a +2 dB trim — and the staging tab sums them automatically. Negative values represent attenuation: a fader pulled down 10 dB is −10, a pad is negative. The running total shows whether any point in the chain would clip a 0 dBFS digital ceiling, or you can set your input to a typical noise floor and track headroom through each stage.
When should I use amplitude gain vs. power gain?
Use amplitude (voltage) gain for almost everything in audio: microphone preamps, channel faders, DAW plug-in trims, op-amp circuits, and any measurement in dBu or dBV. Use power gain for acoustic power ratios (watts in, watts out from a speaker or amplifier), RF/transmitter systems, and antenna gain specs. The formulas differ by a factor of 2 in the exponent (20·log vs 10·log), so applying the wrong one gives you exactly half the dB answer you should get — a common source of confusion when mixing electrical and acoustic measurements.