dB / dBm / W / Vrms Converter

Convert RF power and voltage units quickly with selectable system impedance.

Language English Korean Japanese Chinese

Input type

dBm

System impedance (ohms)

Action

Ready.

dBmN/A

dBWN/A

Watt (W)N/A

Milliwatt (mW)N/A

VrmsN/A

VpeakN/A

VppN/A

IrmsN/A

dBm = 10 * log10(P in mW)
dBW = 10 * log10(P in W)
P = Vrms^2 / Z0

Why This Conversion Matters in Lab and Production

RF teams constantly move between logarithmic and linear units. Instruments, datasheets, and simulation logs do not always use the same representation, so fast and reliable conversion prevents interpretation errors in gain budgets, PA drive planning, and interface-level verification.

Common scenarios

Translate receiver sensitivity in dBm to equivalent Vrms for hardware bring-up checks.
Convert amplifier output limits from watts to dBm for cascade budget spreadsheets.
Estimate current at a given system impedance before selecting attenuators or couplers.

Reference examples at 50 ohms

0 dBm equals 1 mW and about 0.2236 Vrms.
30 dBm equals 1 W and about 7.071 Vrms.
10 W equals 40 dBm and about 22.36 Vrms.

Important caution

Vrms conversion requires the impedance value you select. If the actual load differs from the assumed Z0, computed voltage and current will be wrong even when dBm and watt values are internally consistent.