RF Toolbox: Ham Radio Tools

RF Toolbox puts 53 amateur radio and RF engineering calculators in one fast, offline-friendly app. Design antennas, check SWR, plan filters, read live solar indices and look up codes without switching between websites.

ANTENNA DESIGN
• Dipole, Inverted Vee, Vertical, Ground Plane and J-Pole calculators
• 3-Element Yagi and Full-Wave Loop
• Antenna Visualizer and SWR Chart

RF CALCULATORS & CONVERTERS
• VSWR, Decibel, Ohm's Law and Frequency / wavelength converter
• Coaxial cable properties and coax cable loss
• Doppler shift and unit converter
• Smith Chart: tap to place a point and read impedance, admittance and SWR

FILTERS & COMPONENTS
• Low-pass and high-pass filter design
• Reactance, inductor and air-core inductor calculators

PROPAGATION & TIME
• Solar & Propagation: live solar flux, K-index and A-index from NOAA SWPC with HF band condition estimates
• NVIS antenna planning, UTC world clock and contest timer

LOCATION
• GPS location with Maidenhead grid square
• Grid square, coordinate and distance tools

CODES & REFERENCE
• Q codes, RST, 92 codes, CW abbreviations and NATO phonetic alphabet
• Morse code translator and U.S. band plan
• Callsign prefix reference and a radio practice quiz

RF TOOLBOX PRO (one-time purchase)
Unlock 11 advanced tools with a single purchase. No subscription, and future Pro tools are included:
• 7-Element Yagi, Cubical Quad and Magnetic Loop
• Half-wave and narrowband balun calculators
• Pi and T attenuators, ERP / EIRP
• Link budget, RF exposure screening and radiation pattern

PRIVACY FIRST
• No account and no sign-in
• No ads and no analytics
• Favorites and calculation history stay on your device
• Location is used only when you open GPS Location and is not sent to our servers

Calculations and propagation estimates are planning aids. Always verify antenna safety, RF exposure compliance and your local regulations before transmitting.

Questions or feedback: tech@clk.company

Recent changes:
Welcome to RF Toolbox!
• 53 ham radio and RF calculators in one app
• Antenna design: dipole, vertical, J-pole, Yagi, loop and more
• Smith chart, SWR chart, VSWR, decibel and coax loss tools
• Live solar flux and K-index from NOAA with HF band estimates
• Filters, reactance, Maidenhead grid, distance and callsign tools
• Q codes, Morse, NATO alphabet and U.S. band plan reference
• RF Toolbox Pro: 11 advanced tools, one-time purchase
• No ads, no account required