How to Convert Kilohertz to Megahertz
To convert a frequency measurement from kilohertz to megahertz, divide the frequency value by the conversion factor. Since one kilohertz is equal to 0.001 megahertz, you can use this formula:
The frequency in megahertz is equal to the kilohertz divided by 1,000.
Using the formula: megahertz = kilohertz ÷ 1,000
megahertz = 5 kHz ÷ 1,000 = 0.005 MHz
Therefore, 5 kilohertz equals 0.005 megahertz.
How Many Megahertz Are in a Kilohertz?
There are 0.001 megahertz in one kilohertz.
What Is a Kilohertz?
The kilohertz (symbol: kHz) is a unit of frequency equal to one thousand (103) hertz. The prefix “kilo” denotes a factor of 1,000 in the International System of Units. Kilohertz frequencies are encountered in audio engineering, AM radio broadcasting, and ultrasonic applications. The full range of human hearing (20 Hz to 20,000 Hz) is often expressed as 0.02–20 kHz. Audio sampling rates are commonly 44.1 kHz (CD quality) or 48 kHz (professional audio). In radio broadcasting, the AM (amplitude modulation) band spans approximately 530–1,700 kHz. Longwave radio operates at 148.5–283.5 kHz, and shortwave radio spans 3–30 MHz (3,000–30,000 kHz). In ultrasonics, frequencies in the tens to hundreds of kilohertz are used for industrial cleaning (20–40 kHz), sonar systems (10–100 kHz), and some medical imaging applications. Pest deterrent devices typically operate in the 15–25 kHz range.
One kilohertz is equal to:
- 1,000 hertz (Hz)
- 1,000 cycles per second (cps)
- 0.001 megahertz (MHz)
- 10−6 gigahertz (GHz)
- 60,000 revolutions per minute (RPM)
- 6,283.19 radians per second (rad/s)
What Is a Megahertz?
The megahertz (symbol: MHz) is a unit of frequency equal to one million (106) hertz. The prefix “mega” denotes a factor of 106 in the International System of Units. Megahertz frequencies are central to radio communications, television broadcasting, and early computing. The FM (frequency modulation) radio band spans 87.5–108 MHz in most countries. VHF television channels operate at 54–216 MHz, and UHF television at 470–890 MHz. In computing history, early personal computers (1970s–1990s) had processor clock speeds measured in megahertz. The original IBM PC (1981) ran at 4.77 MHz, and by the late 1990s, processors had reached several hundred MHz before crossing the 1 GHz threshold. In medical imaging, diagnostic ultrasound transducers typically operate at 2–18 MHz, with higher frequencies providing better resolution for shallow structures and lower frequencies providing better penetration for deep structures.
One megahertz is equal to:
- 106 hertz (Hz)
- 1,000 kilohertz (kHz)
- 0.001 gigahertz (GHz)
- 10−6 terahertz (THz)
- 6 × 107 RPM
- 6.28319 × 106 radians per second (rad/s)
Understanding Frequency Units
Frequency is a physical quantity that measures how often a periodic event occurs per unit of time. In the most common usage, it measures the number of complete cycles of oscillation per second. Frequency is the reciprocal of the period (T): f = 1/T.
Different frequency units have evolved to serve different fields and applications. The hertz and its metric multiples dominate physics and electronics, while RPM is standard in mechanical engineering, and radians per second is preferred in mathematical physics and control theory.
Major Unit Families
- SI / Metric units: The hertz (Hz) is the SI unit of frequency, with standard metric prefixes (kHz, MHz, GHz, THz). Each prefix step is a factor of 1,000.
- Cycles per second: The cycle per second (cps) is the original name for the hertz. It is numerically identical (1 cps = 1 Hz) but predates the adoption of the “hertz” name in 1960.
- Revolutions per minute: RPM measures rotational speed and is widely used in mechanical engineering and everyday life. 1 RPM = 1/60 Hz.
- Angular velocity units: Radians per second (rad/s) and degrees per second (°/s) measure angular velocity. One full revolution = 2π rad = 360°, so 1 Hz = 2π rad/s = 360 °/s.
Frequency in Everyday Life
- Sound: Human hearing ranges from about 20 Hz to 20 kHz. Middle C on a piano is 261.6 Hz. Concert pitch A is 440 Hz.
- Electricity: Mains power alternates at 50 Hz (most of the world) or 60 Hz (Americas, parts of Asia).
- Computing: Modern CPUs run at 2–5 GHz. Monitor refresh rates are 60–360 Hz.
- Radio: AM radio: 530–1,700 kHz. FM radio: 87.5–108 MHz. Wi-Fi: 2.4 / 5 / 6 GHz.
- Rotation: Car engines idle at 600–1,000 RPM. Hard drives spin at 5,400–7,200 RPM.
Converting Between Frequency Units
All frequency units measure the same physical quantity (periodic events per unit time), so converting between them involves multiplying by the appropriate conversion factor. The key relationships are:
- 1 Hz = 1 cps (identical units)
- 1 Hz = 60 RPM (one cycle per second = 60 cycles per minute)
- 1 Hz = 2π rad/s ≈ 6.28319 rad/s (one cycle = 2π radians)
- 1 Hz = 360 °/s (one cycle = 360 degrees)
Tips for Frequency Conversions
- For SI metric conversions (Hz, kHz, MHz, GHz, THz), each prefix step is a factor of 1,000. So 1 GHz = 1,000 MHz = 1,000,000 kHz = 109 Hz.
- Hertz and cycles per second are exactly the same unit (1 Hz = 1 cps). The name “hertz” was adopted in 1960 to honour Heinrich Hertz.
- To convert Hz to RPM, multiply by 60. To convert RPM to Hz, divide by 60.
- To convert Hz to rad/s, multiply by 2π (≈ 6.28319). To convert rad/s to Hz, divide by 2π.
- To convert Hz to °/s, multiply by 360. To convert °/s to Hz, divide by 360.
- To convert RPM to rad/s, multiply by 2π/60 (≈ 0.10472). This is one of the most common conversions in mechanical engineering.
- To convert RPM to °/s, multiply by 6 (since 360° ÷ 60 s = 6 °/s per RPM).
- Remember that frequency (f in Hz) and angular frequency (ω in rad/s) are related by ω = 2πf. Many physics equations use ω rather than f.
Kilohertz to Megahertz Conversion Table
The following table shows conversions from kilohertz to megahertz.
| Kilohertz | Megahertz (MHz) |
|---|---|
| 1 kHz | 0.001 |
| 2 kHz | 0.002 |
| 3 kHz | 0.003 |
| 4 kHz | 0.004 |
| 5 kHz | 0.005 |
| 6 kHz | 0.006 |
| 7 kHz | 0.007 |
| 8 kHz | 0.008 |
| 9 kHz | 0.009 |
| 10 kHz | 0.01 |
| 11 kHz | 0.011 |
| 12 kHz | 0.012 |
| 13 kHz | 0.013 |
| 14 kHz | 0.014 |
| 15 kHz | 0.015 |
| 16 kHz | 0.016 |
| 17 kHz | 0.017 |
| 18 kHz | 0.018 |
| 19 kHz | 0.019 |
| 20 kHz | 0.02 |
| 21 kHz | 0.021 |
| 22 kHz | 0.022 |
| 23 kHz | 0.023 |
| 24 kHz | 0.024 |
| 25 kHz | 0.025 |
| 26 kHz | 0.026 |
| 27 kHz | 0.027 |
| 28 kHz | 0.028 |
| 29 kHz | 0.029 |
| 30 kHz | 0.03 |
| 31 kHz | 0.031 |
| 32 kHz | 0.032 |
| 33 kHz | 0.033 |
| 34 kHz | 0.034 |
| 35 kHz | 0.035 |
| 36 kHz | 0.036 |
| 37 kHz | 0.037 |
| 38 kHz | 0.038 |
| 39 kHz | 0.039 |
| 40 kHz | 0.04 |