Antenna Wavelength Calculator
Enter a frequency in MHz to calculate antenna lengths
How to Use
- Enter frequency in MHz (e.g., 145.000 for 2m band)
- Results are calculated automatically or click Calculate
- All measurements are in inches for quarter-wave, half-wave, and 5/8-wave antennas
- Formula: Length = (Speed of Light ÷ Frequency × 1000000) × Wave Factor × 39.37008
VSWR Calculator
Calculate Voltage Standing Wave Ratio from forward and reflected power
VSWR Guidelines
- 1.0:1 - Perfect match (no reflected power)
- 1.5:1 - Good match (90% power transfer)
- 2.0:1 - Acceptable (80% power transfer)
- 3.0:1 - Poor match (50% power transfer)
dB Power Calculator
Convert between power (watts) and dB measurements
dB Reference Information
- dBW - Decibels relative to 1 watt
- dBm - Decibels relative to 1 milliwatt (dBW + 30)
- 10mW = 10dBm = 0dBW
- 100W = 50dBm = 20dBW
Frequency Band Identifier
Enter a frequency to identify which radio band it belongs to
Common Radio Bands
- 160m: 1.8-2.0 MHz (Top Band)
- 80m: 3.5-4.0 MHz (Phone Band)
- 40m: 7.0-7.3 MHz
- 20m: 14.0-14.35 MHz
- 17m: 18.068-18.168 MHz
- 15m: 21.0-21.45 MHz
- 12m: 24.89-24.99 MHz
- 10m: 28.0-29.7 MHz (DX Band)
- 6m: 50-54 MHz (Magic Band)
- 2m: 144-148 MHz (VHF)
- 70cm: 420-450 MHz (UHF)
Link Budget Calculator
Calculate received signal power in a radio link
Link Budget Formula
Pr = Pt + Gt + Gr - L
- Pr: Received power (dBm)
- Pt: Transmit power (dBm)
- Gt: Transmit antenna gain (dBi)
- Gr: Receive antenna gain (dBi)
- L: Path loss (dB)