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⚡ dB to Volts Calculator
Convert decibel voltage levels into volts using dBV, dBu, or a custom reference voltage. You can also reverse the calculation and convert volts back into dBV or dBu.Enter the voltage that represents 0 dB for your custom reference.Example: enter +4 for +4 dBu or -10 for -10 dBV.Conversion Result
Voltage —Volts —Millivolts —Reference —Common Audio Voltage ReferencesLevel Reference Approx. Voltage 0 dBV 1 V RMS 1.000 V RMS +4 dBu 0.775 V RMS 1.228 V RMS 0 dBu 0.775 V RMS 0.775 V RMS -10 dBV 1 V RMS 0.316 V RMS How does the dB to Volts Calculator work?
Decibels describe a ratio rather than an absolute voltage by themselves. To convert a decibel value into volts, you need to know the voltage reference represented by 0 dB.
For voltage ratios, the conversion is:
Voltage = Reference Voltage × 10(dB ÷ 20)
For example, 0 dBV uses a reference of 1 volt RMS, so 0 dBV equals 1 V RMS. A level of +6 dBV is approximately 2 volts RMS.
dBu uses a different reference: 0 dBu corresponds to approximately 0.775 V RMS. This means +4 dBu, a common professional audio reference level, corresponds to approximately 1.228 V RMS.
The reverse calculation converts voltage into decibels using:
dB = 20 × log10(Voltage ÷ Reference Voltage)Tip: Always check which decibel reference is being used before converting a value to voltage. +4 dBu and +4 dBV are not the same voltage because dBu and dBV use different reference voltages. Also remember that dBFS, which is commonly used in digital audio, cannot be universally converted directly into volts without knowing the hardware's analog calibration. -
A dB to Volts Calculator helps audio engineers, producers, musicians, electronics enthusiasts, and studio technicians convert decibel-based voltage levels into actual electrical voltage values.
Decibels are relative measurements, so a dB value by itself does not tell you an absolute voltage. To convert decibels to volts, the calculation needs a reference voltage representing 0 dB.
Two common references in audio are dBV and dBu.
dBV uses 1 volt RMS as its reference, meaning that 0 dBV equals exactly 1 V RMS. A positive dBV value represents a voltage above 1 volt, while a negative dBV value represents a voltage below 1 volt.
dBu uses approximately 0.775 V RMS as its reference. For example, the commonly used professional audio reference level of +4 dBu corresponds to approximately 1.228 V RMS.
The calculator can also use a custom reference voltage. This is helpful when working with equipment, measurement systems, or specifications that define 0 dB using a different voltage reference.
To convert decibels into voltage, the calculator uses the voltage-ratio formula:
Voltage = Reference Voltage × 10^(dB ÷ 20)
You can also reverse the calculation and convert a known voltage into a decibel value using:
dB = 20 × log10(Voltage ÷ Reference Voltage)
This type of conversion can be useful when working with audio interfaces, mixers, preamps, amplifiers, signal processors, test equipment, studio electronics, gain staging, and analog audio specifications.
It is important to distinguish dBu and dBV from dBFS. dBFS is a digital level measurement referenced to digital full scale. There is no single universal conversion from dBFS to volts because the relationship depends on the analog calibration and maximum output or input level of the particular audio hardware.
Also keep in mind that the voltage values in this tool are treated as RMS voltage levels, which is the convention commonly used with dBu and dBV audio specifications.
Tip: Always identify the reference before converting a decibel value. For example, +4 dBu and +4 dBV do not represent the same voltage. If a specification simply says "dB" without identifying the reference, look for additional documentation before assuming it represents dBu or dBV.
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