rftools.io

dBm to Watts Power Converter

Convert RF power between dBm, Watts, milliwatts, dBW, dBμV, and RMS volts into 50Ω. Essential for link budgets, amplifier analysis, and RF system design.

Loading calculator...

Formula

P(W)=10dBm/10×10−3,V=P×50P(W) = 10^{dBm/10} \times 10^{-3}, \quad V = \sqrt{P \times 50}
P — Power (W or mW)
dBm — Power in dBm (dBm)
dBW — Power in dBW (= dBm − 30) (dBW)
V — RMS voltage into 50Ω (V)

How It Works

The decibel-milliwatt (dBm) is a logarithmic power ratio referenced to 1 milliwatt, commonly used in telecommunications and RF engineering to express signal strength. Converting dBm to watts requires applying an exponential calculation that scales the logarithmic representation back to absolute power measurements. This conversion is critical for understanding signal levels, antenna performance, and power budgets in communication systems.

Worked Example

Problem: Convert 20 dBm to watts Solution: 1. Apply formula P(W) = 10^(dBm/10) × 10⁻³ 2. P(W) = 10^(20/10) × 10⁻³ 3. P(W) = 10^2 × 0.001 4. P(W) = 100 × 0.001 5. P(W) = 0.1 watts

Practical Tips

  • ✓Always verify the reference impedance (typically 50Ω)
  • ✓Use a calculator with scientific notation support
  • ✓Double-check unit conversions and scaling factors

Common Mistakes

  • ✗Forgetting to divide dBm value by 10 before exponentiating
  • ✗Incorrectly applying the 10⁻³ scaling factor
  • ✗Confusing dBm with absolute power measurements

Frequently Asked Questions

Related Calculators

RF

dBm Converter

Convert dBm to watts, milliwatts, dBW, dBμV, and volts RMS. Essential RF power unit conversion tool for signal levels and link budgets.

RF

Link Budget

Calculate RF link budget: transmit power, free space path loss, antenna gains, and received signal level. Determine link margin and maximum range.

Antenna

EIRP / ERP

Calculate Effective Isotropic Radiated Power (EIRP) and ERP from transmit power, cable loss, and antenna gain. Check compliance against FCC, ETSI, and ISM-band regulatory limits.

Convert

Frequency ↔ Wavelength

Convert frequency to wavelength in any medium. Calculates full, half, and quarter wavelengths for antenna design, transmission line, and RF system planning.

Convert

Temperature Converter

Convert temperature between Celsius, Fahrenheit, Kelvin, Rankine, and Réaumur scales. Useful for thermal analysis, datasheet comparison, and engineering calculations.

Convert

AWG Wire Gauge

Convert AWG wire gauge to diameter (mm/inches), cross-sectional area (mm²), resistance per meter, and approximate current carrying capacity.