Frequency Converter

Convert between different frequency units including Hz, kHz, MHz, GHz, THz, and RPM

Frequency Converter

Common Frequency Conversions

1 kHz = 1,000 Hz
1 MHz = 1,000 kHz
1 GHz = 1,000 MHz
1 THz = 1,000 GHz
1 Hz = 60 RPM
1 RPM = 0.0167 Hz

Complete Frequency Conversion Guide

Comprehensive guide to frequency measurements, the electromagnetic spectrum, and professional applications

Understanding Frequency Units

SI Frequency Units

  • Hertz (Hz): 1 cycle per second, SI base unit
  • Kilohertz (kHz) = 1,000 Hz
  • Megahertz (MHz) = 1,000,000 Hz
  • Gigahertz (GHz) = 1,000,000,000 Hz
  • Terahertz (THz) = 10¹² Hz
  • Period (T) = 1/f (seconds per cycle)

Rotational & Other Units

  • RPM (revolutions per minute) = Hz ÷ 60
  • RPS (revolutions per second) = Hz
  • Radians per second (rad/s) = 2π × Hz
  • BPM (beats per minute) used in music/medicine = Hz ÷ 60
  • Angular frequency ω = 2πf

Essential Conversion Factors

Frequency Conversions

  • 1 kHz = 1,000 Hz
  • 1 MHz = 1,000 kHz
  • 1 GHz = 1,000 MHz
  • 1 THz = 1,000 GHz
  • 1 Hz = 60 RPM
  • 1 RPM = 0.01667 Hz

The Radio Spectrum

  • ELF 3–30 Hz (power lines, submarines)
  • VLF 3–30 kHz (navigation)
  • LF 30–300 kHz (AM radio)
  • MF 300 kHz–3 MHz (AM broadcast)
  • HF 3–30 MHz (shortwave)
  • VHF 30–300 MHz (FM, TV)
  • UHF 300 MHz–3 GHz (cellular, WiFi)
  • SHF 3–30 GHz (radar, satellite)

Audio & Light

  • Infrasound: below 20 Hz
  • Human hearing: 20 Hz – 20 kHz
  • Ultrasound: above 20 kHz
  • Visible light: 430–770 THz
  • Infrared: 300 GHz – 430 THz
  • Ultraviolet: 770 THz – 30 PHz
  • X-rays: 30 PHz – 30 EHz

Professional Applications

Electronics & Computing

  • CPU clock speed (GHz)
  • System bus frequency
  • Oscillator crystals
  • Signal processing
  • ADC/DAC sampling rates
  • RF circuit design
  • PCB trace impedance at high frequency

Telecommunications

  • 4G LTE: 700 MHz – 2.6 GHz
  • 5G mmWave: 24–100 GHz
  • WiFi: 2.4 GHz and 5 GHz
  • Bluetooth: 2.4 GHz
  • GPS L1: 1.575 GHz
  • FM radio: 87.5–108 MHz
  • AM radio: 535–1,705 kHz

Audio Engineering

  • Bass frequencies: 20–250 Hz
  • Midrange: 250 Hz – 4 kHz
  • Treble: 4–20 kHz
  • Concert A: 440 Hz
  • Middle C: 261.6 Hz
  • Speaker crossover points
  • Room acoustic resonances
  • Noise-canceling filter design

Medicine & Industry

  • Ultrasound imaging: 2–18 MHz
  • MRI: 64 MHz (1.5T), 128 MHz (3T)
  • TENS therapy: 1–150 Hz
  • Motor speed control (RPM)
  • Vibration analysis (Hz)
  • Quartz watch crystal: 32,768 Hz
  • Power grid: 50 Hz (EU) or 60 Hz (US)

Frequency Measurement Best Practices

Measurement Techniques

  • Use oscilloscopes for visualizing waveforms
  • Frequency counters for precision measurement
  • Spectrum analyzers for multi-frequency signals
  • Lock-in amplifiers for weak signals in noise
  • Always match probe bandwidth to signal frequency

Interference & Safety

  • EMI shielding for sensitive circuits
  • Keep digital and analog grounds separate
  • Frequency coordination for radio transmitters (licensed spectrum)
  • ESD protection for high-frequency components
  • Avoid harmonics in power supply design

Frequency Examples by Category

Audio & Music

  • Lowest pipe organ note: 16 Hz
  • Bass guitar lowest: 41 Hz (E1)
  • Human voice male: 85–180 Hz
  • Human voice female: 165–255 Hz
  • Concert A4: 440 Hz
  • Highest piano key: 4,186 Hz
  • Bat echolocation: 20–200 kHz

Wireless & Communications

  • AM radio: 535–1,705 kHz
  • FM radio: 87.5–108 MHz
  • WiFi 2.4 GHz channel: 2,412–2,484 MHz
  • LTE band 7: 2,620 MHz
  • 5G n261: 27.5 GHz
  • Microwave oven: 2.45 GHz
  • GPS L1: 1,575.42 MHz

Everyday & Industrial

  • Power grid (EU): 50 Hz
  • Power grid (US): 60 Hz
  • Human heart (resting): 1.0–1.3 Hz (60–80 BPM)
  • PC CPU: 3–5 GHz
  • Quartz watch: 32,768 Hz
  • Helicopter rotor: 3–5 Hz
  • Railway catenary: 16.7 Hz (some EU)

Frequently Asked Questions

What is frequency?
Frequency is the number of times a repeating event occurs per unit of time. It is measured in hertz (Hz), where 1 Hz = 1 cycle per second. Frequency applies to sound waves, electromagnetic waves, electrical signals, mechanical vibrations, and any other periodic phenomenon.
How does frequency relate to wavelength?
Frequency and wavelength are inversely related through the wave’s propagation speed: v = f × λ. For electromagnetic waves in free space (c = 299,792,458 m/s), a higher frequency means a shorter wavelength. For example, FM radio at 100 MHz has a wavelength of about 3 meters, while visible light at 500 THz has a wavelength of about 600 nanometers.
What is the difference between Hz and RPM?
Both describe how often something repeats, but in different time bases. Hz counts cycles per second; RPM counts revolutions per minute. To convert RPM to Hz divide by 60. For example, a hard drive spinning at 7,200 RPM = 120 Hz. To convert Hz to RPM, multiply by 60.
What frequency is WiFi?
WiFi operates on two main bands: 2.4 GHz (channels 1–14, spanning roughly 2,412–2,484 MHz) and 5 GHz (channels 36–165, spanning 5,180–5,850 MHz). Wi-Fi 6E and Wi-Fi 7 also use the new 6 GHz band (5,925–7,125 MHz). Higher bands offer faster speeds but shorter range.
Why do some countries use 50 Hz and others 60 Hz for power?
The split dates to the late 1800s when Tesla (50 Hz, later standardized in Europe) and Westinghouse/GE (60 Hz, adopted in North America) built competing power systems. Once infrastructure was in place it became too costly to change, so the world settled into two camps: most of Europe, Africa, Asia, and Australia use 50 Hz; North America and parts of South America use 60 Hz.
What is the audible frequency range for humans?
Healthy young adults can hear from approximately 20 Hz (deep bass) to 20,000 Hz (20 kHz). This range narrows with age — high-frequency hearing loss is common above 50 years. Dogs hear up to about 65 kHz, and bats use echolocation at 20–200 kHz, well beyond human perception.