General EE Utilities
DBM / WATTS / VOLTS CONVERTER
Convert between dBm, watts, and volts (RMS) for any impedance. Essential for RF, telecom, and signal-level work.
Convert between dBm, watts, and volts RMS for any impedance. Enter a value in any unit and instantly see all equivalent representations — including dBW, dBV, dBµV, peak voltage, and peak-to-peak voltage. Adjustable impedance for 50Ω, 75Ω, 300Ω, and custom values.
Convert From
Input Value
Conversion Results
dBm
0.000
Watts
1.0000 mW
VRMS
223.6068 mV
at Z = 50 Ω
dBW
-30.000
dBV
-13.010
dBµV
106.990
Vpeak
316.2278 mV
Vpeak-to-peak
632.4555 mV
Common RF Power Levels
Click a row to load the value into the converter.
| Level | Power | VRMS (50Ω) | Description |
|---|---|---|---|
| +60 dBm | 1.000 kW | 223.60680 V | 1 kW — High-power broadcast transmitter |
| +50 dBm | 100.0000 W | 70.71068 V | 100 W — Amateur radio HF transmitter |
| +40 dBm | 10.0000 W | 22.36068 V | 10 W — Typical handheld radio |
| +30 dBm | 1.0000 W | 7.07107 V | 1 W — 0 dBW reference |
| +20 dBm | 100.0000 mW | 2.23607 V | 100 mW — Max Wi-Fi transmit (US) |
| +10 dBm | 10.0000 mW | 707.1068 mV | 10 mW — Bluetooth Class 1 |
| 0 dBm | 1.0000 mW | 223.6068 mV | 1 mW — dBm reference point |
| −10 dBm | 100.000 µW | 70.7107 mV | 100 µW — Strong received signal |
| −30 dBm | 1.000 µW | 7.0711 mV | 1 µW — Typical wireless signal |
| −50 dBm | 10.000 nW | 707.107 µV | 10 nW — Good Wi-Fi signal |
| −70 dBm | 100.000 pW | 70.711 µV | 100 pW — Weak Wi-Fi signal |
| −90 dBm | 1.000 pW | 7.071 µV | 1 pW — Minimum usable Wi-Fi |
| −110 dBm | 1.000e-14 W | 707.107 nV | 0.01 pW — GPS signal at receiver |
| −174 dBm | 3.981e-21 W | 4.462e-10 V | Thermal noise floor (1 Hz BW, 290K) |
dBm / Watts / Volts Converter Results
Generated by calpak-usa.com/Resources/dBm-Watts-Volts-Converter
| dBm | 0.000 dBm |
| Power | 1.0000 mW |
| V (RMS) | 223.6068 mV |
| Impedance | 50 Ω |
| dBW | -30.000 |
| dBV | -13.010 |
| dBµV | 106.990 |
| V (peak) | 316.2278 mV |
| V (peak-to-peak) | 632.4555 mV |
For reference only. Assumes sinusoidal signal and matched impedance.
Formulas Used
The converter keeps all power, voltage, and logarithmic units synchronized from one source input.
\[P(W) = 10^{\left(\frac{dBm}{10}\right)} \times 10^{-3}\]
\[dBm = 10 \log_{10}\left(\frac{P}{10^{-3}}\right)\]
\[V_{RMS} = \sqrt{(PZ)}\]
\[P = \frac{V_{RMS}^2}{Z}\]
\[dBW = dBm - 30,\; dBV = 20\log_{10}(V_{RMS}),\; dB\mu V = dBV + 120\]
\[V_{peak} = \sqrt{(2)}\,V_{RMS},\; V_{pp} = 2V_{peak}\]
Z is system impedance in ohms. Voltage conversions assume a sinusoidal waveform and matched impedance.
Understanding dBm, Watts, and Volts
dBm (decibels relative to 1 milliwatt) is the standard unit for expressing power levels in RF engineering, telecommunications, and signal processing. Unlike linear units, dBm uses a logarithmic scale that compresses the enormous dynamic range of real-world signals into manageable numbers. A typical wireless system might deal with signals ranging from −174 dBm (thermal noise floor) to +60 dBm (1 kW transmitter) — a ratio of over 1023 that would be unwieldy in linear units.
Converting between dBm and watts is straightforward: 0 dBm equals 1 milliwatt, and every 10 dB increase represents a 10× increase in power. So +10 dBm = 10 mW, +20 dBm = 100 mW, +30 dBm = 1 W, and so on. Going the other direction, −10 dBm = 100 µW, −20 dBm = 10 µW. A useful shortcut: +3 dB doubles the power, −3 dB halves it.
Voltage conversion requires knowing the system impedance. In RF systems, 50Ω is standard for most test equipment and coaxial cables. Video and cable TV systems typically use 75Ω. Audio systems may use 600Ω. The relationship is VRMS = √(P × Z), where P is in watts and Z is the impedance in ohms.
For aerospace and defense RF systems, accurate power level calculations are critical for link budget analysis, receiver sensitivity specifications, and EMI/EMC compliance testing. Calpak USA's engineering team has experience with military-grade RF and mixed-signal designs. Contact us for design support.
Quick Reference: dB Rules of Thumb
| Change (dB) | Power Ratio | Voltage Ratio |
|---|---|---|
| +3 dB | × 2 | × 1.414 |
| +6 dB | × 4 | × 2 |
| +10 dB | × 10 | × 3.162 |
| +20 dB | × 100 | × 10 |
| −3 dB | × 0.5 | × 0.707 |
| −10 dB | × 0.1 | × 0.316 |
| −20 dB | × 0.01 | × 0.1 |
Remember: dB is a ratio. +3 dB always doubles power regardless of the starting level. For voltage, +6 dB doubles the amplitude (since power is proportional to V²).
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