Oscilloscope & Waveform Laboratory Solver
dBm to Vpp Calculator
Convert RF power in dBm to Peak-to-Peak Voltage (Vpp), Peak Voltage (Vpk), and RMS Voltage (Vrms) across 50Ω and 75Ω loads for sinusoidal and modulated signals.
Logarithmic
dBm
Oscilloscope Trace
Vpp
Peak-to-Peak (mVpp)
632.46 mVpp
Peak Voltage (Vpk)
0.3162 Vpk
RMS Voltage (Vrms)
0.2236 Vrms
Linear Power
1.000 mW
Oscilloscope Calibration Table
dBm to Vpp and Vrms at 50 Ω (Sine Wave)
| Power (dBm) | Linear Power | Vrms (50 Ω) | Peak Voltage (Vpk) | Peak-to-Peak (Vpp) | Typical Application |
|---|---|---|---|---|---|
| +30 dBm | 1.000 Watt | 7.071 Vrms | 10.00 Vpk | 20.00 Vpp | 1 Watt Transceiver Output |
| +20 dBm | 100.0 mW | 2.236 Vrms | 3.162 Vpk | 6.325 Vpp | Wi-Fi Router Max EIRP |
| +10 dBm | 10.00 mW | 0.707 Vrms | 1.000 Vpk | 2.000 Vpp | Standard Lab Signal Generator Test Level |
| 0 dBm | 1.000 mW | 0.2236 Vrms | 0.3162 Vpk | 632.5 mVpp | Universal 0 dBm Baseline Reference |
| −10 dBm | 100.0 µW | 70.71 mVrms | 100.0 mVpk | 200.0 mVpp | Mixer Local Oscillator (LO) Leakage |
| −30 dBm | 1.000 µW | 7.071 mVrms | 10.00 mVpk | 20.00 mVpp | Spectrum Analyzer 1 dB Compression Max |
Knowledge Base
Frequently Asked Questions
Common questions about RF power conversions, negative dBm, and voltage calculations.
For a pure sinusoidal RF signal across 50 Ω: 1) P(W) = 10^((dBm − 30)/10), 2) V_rms = √(P × 50), 3) V_pp = 2 × √2 × V_rms ≈ 2.8284 × V_rms. Combining into one formula: V_pp = 2.8284 × √(0.05 × 10^(dBm/10)).
At 50 Ω, 0 dBm (1.0 mW) produces an RMS voltage of 0.2236 Vrms (223.6 mV). Multiplying by 2√2 yields 0.6325 Vpp (632.5 mVpp).
+10 dBm (10 mW) produces 0.7071 Vrms, which corresponds to exactly 2.000 Vpp (2,000 mVpp).
A standard benchtop oscilloscope input has a high impedance of 1 MΩ. When connected to a 50 Ω RF generator without an internal or external 50 Ω feedthrough termination, the transmission line is open-circuit terminated (Γ = +1.0), causing full voltage reflection that doubles the observed Vpp (+6.02 dB error).
Digital signals (such as OFDM in Wi-Fi 6 or 5G NR) have a high Peak-to-Average Power Ratio (PAPR ≈ 8 to 11 dB). Instantaneous peak voltages can reach 3 to 4 times the average Vrms, requiring additional ADC headroom to avoid clipping.