Audio Level Converter

Free tool to convert dBu, dBV, dBFS, dBm, volts and watts. No sign-up

Type a value and choose its unit, or load a common level like +4 dBu or −10 dBV.
Set the impedance if you want dBm and power (600 Ω is the classic value for dBu and dBm to match).
Choose the dBFS alignment of your converter or interface, or type your own.
Read the table: your unit is highlighted and every other unit is shown, from dBu to watts.
Download the results as CSV or copy them as text.

dBu and dBV do not depend on impedance: dBm and power do, so set the impedance for them. Peak and peak-to-peak values assume a sine wave. dBFS depends on the alignment of your converter or interface: pick one or type your own.

Nothing is saved or uploaded: everything stays in your browser. Download or copy your results before closing the page. 0 dBu is 0.7746 V RMS, the voltage that gives 1 mW across 600 Ω, so dBu and dBm are the same only at 600 Ω. The dBFS alignment presets are common references, not a rule: check the manual of your interface.

How do you convert dBu to dBV, and what is +4 dBu in volts?

dBu is referenced to 0.775 V RMS and dBV to 1 V RMS, so dBV is about 2.2 dB lower than dBu for the same signal. Pro line level, +4 dBu, is 1.228 V RMS or +1.78 dBV, while consumer line level, −10 dBV, is 0.316 V RMS or −7.78 dBu. dBFS has no fixed voltage: it depends on how the converter is aligned, for example −18 dBFS = +4 dBu or −20 dBFS = +4 dBu. This free converter turns any of these units into all the others, with the impedance for dBm and power, and the dBFS alignment, set by you.

Why are there so many decibel units for audio levels?

A decibel is not a unit of measurement by itself: it only says how many times one level is bigger or smaller than another. Each unit with a letter after dB names its reference. dBu uses 0.775 volts, dBV uses 1 volt, dBm uses one milliwatt, and dBFS uses the highest level a digital system can record. Professional gear works around +4 dBu and consumer gear around −10 dBV, which is why plugging one into the other changes the level by about 12 dB. dBFS is the odd one out, because the voltage that corresponds to 0 dBFS depends on the interface, so the tool asks you for it.

Made by Luca Martone, sound designer and live sound engineer based in Turin.
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