Voltage ratio to decibels
Type a value in × V to get it in dB instantly.
That's 4× as much as a hundred times, while a million times is 2,500× higher. That is 400× the power, or 20× the voltage.
Convert the other way: dB to × V
What it means
How much is that?
These are plain ratio decibels. Decibels with a letter after them — dBm, dBW, dBµV — are levels against a fixed reference, which is a different page.
The math
How to convert × V to dB
Decibels are logarithmic, and power and amplitude use different multipliers: dB = 10 × log₁₀(power ratio) but dB = 20 × log₁₀(voltage ratio). Back the other way, the ratio is 10^(dB ÷ 10) or 10^(dB ÷ 20).
Example: 20 × V = 26.0206 dB.
Every unit
Your gain in every unit
Tables
× V to dB conversion table
| × V | dB |
|---|---|
| 0.1 × V | -20 dB |
| 0.316 × V | -10.0063 dB |
| 0.501 × V | -6.00325 dB |
| 0.708 × V | -2.99933 dB |
| 1 × V | 0 dB |
| 1.41 × V | 2.98438 dB |
| 2 × V | 6.0206 dB |
| 3.16 × V | 9.99374 dB |
| 10 × V | 20 dB |
| 31.6 × V | 29.9937 dB |
| 100 × V | 40 dB |
| 1,000 × V | 60 dB |
dB to × V conversion table
| dB | × V |
|---|---|
| -20 dB | 0.1 × V |
| -10 dB | 0.316228 × V |
| -6 dB | 0.501187 × V |
| -3 dB | 0.707946 × V |
| 0 dB | 1 × V |
| 3 dB | 1.41254 × V |
| 6 dB | 1.99526 × V |
| 10 dB | 3.16228 × V |
| 20 dB | 10 × V |
| 30 dB | 31.6228 × V |
| 40 dB | 100 × V |
| 60 dB | 1,000 × V |
Quick answers
Quick answers
- How many dB is 1 × V?
- 1 × V is 0 dB.
- How many dB is 10 × V?
- 10 × V is 20 dB.
- How many dB is 20 × V?
- 20 × V is 26.0206 dB.
The units
About these units
Voltage ratio (× V)
How many times the voltage or pressure: 10 dB is 3.16 times.
Decibels (dB)
The standard logarithmic ratio: ten times the log of a power ratio.
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