Cycles per Second
One hertz means one cycle per second. The unit scales like the metric system: 1 kHz = 1,000 Hz, 1 MHz = 1,000,000 Hz, 1 GHz = 1,000,000,000 Hz. Audio ranges from about 20 Hz to 20,000 Hz; FM radio sits around 100 MHz; modern CPUs run at several GHz.
Converting
Each step is a factor of 1,000, so converting Hz to kHz divides by 1,000, kHz to MHz divides by 1,000, and so on — identical to moving a decimal point three places.
Reference
| Unit | Hertz | Typical use |
|---|---|---|
| 1 Hz | 1 | heartbeat |
| 1 kHz | 1,000 | audio |
| 1 MHz | 1,000,000 | radio |
| 1 GHz | 1,000,000,000 | CPU, Wi-Fi |