Frequency Converter
Convert Hz, kHz, MHz, GHz with period and wavelength calculator
Quick Presets
Convert Frequency
Musical Notes (A4 = 440 Hz)
Common Frequencies
Frequently Asked Questions
How do I convert Hz to kHz, MHz, and GHz?
1 kHz = 1,000 Hz, 1 MHz = 1,000,000 Hz, 1 GHz = 1,000,000,000 Hz. To convert up, divide by 1,000 at each step. Example: 2,400,000,000 Hz = 2,400,000 kHz = 2,400 MHz = 2.4 GHz (standard WiFi frequency). A 3.5 GHz CPU runs 3,500,000,000 clock cycles per second. Human hearing spans 20 Hz to 20,000 Hz (20 kHz).
What is the period of a wave and how does it relate to frequency?
Period (T) is the time for one complete cycle, and it equals 1/frequency. Example: a 440 Hz tuning fork (the musical note A4) has a period of 1/440 = 0.002273 seconds = 2.273 milliseconds. A 60 Hz AC power cycle has a period of 1/60 ≈ 16.67 ms. A 2.4 GHz WiFi signal has a period of 1/2,400,000,000 ≈ 0.417 nanoseconds.
What is the standard tuning frequency for the musical note A4?
The standard concert pitch is A4 = 440 Hz, adopted internationally in 1939. All other notes are derived from this anchor using the equal temperament system, where each semitone is a frequency ratio of 2^(1/12) ≈ 1.05946. So A5 = 880 Hz (double), A3 = 220 Hz (half), and middle C (C4) ≈ 261.63 Hz.
What is the difference between 2.4 GHz and 5 GHz WiFi?
WiFi operates at 2.4 GHz (2,400 MHz) and 5 GHz (5,000 MHz) radio frequencies. The 2.4 GHz band has longer range and better wall penetration but is more congested (shared with Bluetooth, microwaves, baby monitors). The 5 GHz band is faster and less congested but has shorter range. The frequency difference does not affect speed directly — channel width and protocol matter more.
What is the difference between AC power frequency in the US (60 Hz) and Europe (50 Hz)?
US and Canada use 60 Hz AC power at 120V, while most of Europe, Asia, and Africa use 50 Hz at 220–240V. The 60 Hz frequency means the current changes direction 60 times per second. 50 Hz means 50 times. Most modern electronics (phone chargers, laptops) work on both frequencies. The difference matters for motors (fans, clocks run slightly slower on 50 Hz) and for appliances with transformers.