Professional Audio Level Converter — dBu, dBV, Volts & dBFS

Convert line levels, interface specifications, and meter readings between dBu, dBV, volts RMS, millivolts RMS, and calibrated dBFS. Your values stay in this browser.

Source level and calibration

Enter the RMS voltage or level shown by the selected unit.

Use the relationship stated in your converter, recorder, console, or interface manual.

Calibration: 0 dBFS = +24.00 dBu = 12.28292 V RMS

dBFS has no universal voltage. Changing this value changes only the digital/analog mapping, not the dBu ↔ dBV ↔ volts relationship.

Equivalent audio level

RMS voltage

1.228292 V RMS
+4.00 dBu maps to −20.00 dBFS under the selected calibration.
dBu+4.00 dBu
dBV+1.79 dBV
Millivolts RMS1,228.292 mV
Calibrated digital level−20.00 dBFS
Sine-wave peak1.737068 V peak
Sine-wave peak-to-peak3.474135 V p-p

Peak voltage assumes a sine wave (crest factor √2).

Private by design: calculation and export run locally; the tool does not upload or store your input.

Advertisement

How to use the audio level converter

  1. Select the unit printed in your equipment manual, measurement, or meter.
  2. Enter the audio level. Voltage inputs must be greater than zero; dBFS inputs cannot exceed 0.
  3. Set the analog level your device maps to 0 dBFS. Use a preset only when it matches the device’s stated alignment.
  4. Read the analog equivalents, calibrated digital level, and sine-wave peak voltages. Copy or export the result if needed.
Important: do not infer a hardware calibration from the nominal operating level alone. “+4 dBu equipment” does not necessarily mean +4 dBu equals −20 dBFS; check the maximum input/output specification or alignment documentation.

dBu, dBV, volts, and dBFS formulas

dBu from volts: dBu = 20 × log10(VRMS / 0.775)

Volts from dBu: VRMS = 0.775 × 10^(dBu / 20)

dBV from volts: dBV = 20 × log10(VRMS / 1 V)

Calibrated dBFS: dBFS = dBu − dBu at 0 dBFS

Sine-wave voltage: Vpeak = VRMS × √2; Vp-p = 2 × Vpeak

dBu and dBV are logarithmic voltage levels. The dBu reference is 0.775 V RMS, while the dBV reference is 1 V RMS. This creates a constant difference of approximately 2.214 dB: for one physical voltage, its dBu value is about 2.214 dB higher than its dBV value.

dBFS is different. It is a digital ratio relative to the maximum coding level, so an A/D or D/A converter must define the corresponding analog voltage. If +4 dBu aligns with −20 dBFS, adding 20 dB makes full scale +24 dBu. If +4 dBu instead aligns with −18 dBFS, full scale is +22 dBu.

Common analog level reference points

LeveldBVVoltage RMSContext
+24 dBu+21.79 dBV12.28 VExample full-scale analog capability
+18 dBu+15.79 dBV6.16 VExample full-scale or headroom reference
+4 dBu+1.79 dBV1.228 VCommon professional nominal level
0 dBu−2.21 dBV0.775 VdBu reference voltage
−7.79 dBu−10.00 dBV0.316 VCommon consumer nominal level

These are voltage equivalents, not guaranteed clipping points. Published maximum levels can vary with balanced/unbalanced connection, load, gain setting, and device mode.

Assumptions, references, and limits

  • RMS voltage: dBu and dBV results use RMS voltage and do not require a load impedance. This is not a dBm power calculation.
  • 0.775 V reference: the formulas follow the standard audio convention. Analog Devices likewise defines dBu relative to 0.775 V and dBV relative to 1 V in its VRMS/dBu/dBV conversion reference.
  • Digital alignment: the EBU recommends a digital alignment level 18 dB below maximum coding level, but the corresponding analog level depends on the system. See EBU R 068.
  • dBFS convention: the tool treats dBFS as a level difference below the entered 0 dBFS analog calibration. It does not infer a digital waveform’s RMS value from its sample peak or change the calibration for different waveforms.
  • Waveform crest factor: peak and peak-to-peak outputs assume an undistorted sine wave. Square, pulse, noise, and programme signals can have different peaks for the same RMS level.
  • Practical accuracy: displayed precision is useful for conversion and documentation, but it does not imply that meters, analog stages, or calibration measurements are equally precise.

This calculator is for level conversion and planning, not electrical safety or equipment certification. Confirm actual maximum levels, wiring, load requirements, and calibration in the manufacturer’s documentation before connecting hardware.

Professional audio level FAQ

How do I convert dBu to volts?

Multiply 0.775 V by 10 raised to dBu divided by 20. For example, +4 dBu is approximately 1.228 V RMS.

What is the difference between dBu and dBV?

dBu references 0.775 V RMS; dBV references 1 V RMS. The same voltage therefore reads about 2.214 dB higher in dBu.

Can dBFS be converted directly to volts?

Only with a known calibration. dBFS describes digital level relative to full scale and does not define one universal analog voltage.

Is +4 dBu the same as −20 dBFS?

Only under a calibration where 0 dBFS equals +24 dBu. Select a different calibration if your equipment states another alignment.

Are the peak values valid for every waveform?

No. V peak and V peak-to-peak assume a sine wave. Other crest factors produce different peak voltage at the same RMS level.

Does this converter upload or store my levels?

No. Calculation, copying, and CSV generation happen locally in your browser.

Explore more tools