It is non-SI multiple of the frequency unit hertz.
Symbol : zHz
So 1 zeptohertz = 1.00E-21 hertz.
Example : 25 zeptohertz = 1.00E-21 X 25 Hertz.
Or we can say, 25zHz = 2.5E-20 Hz.
Use this conversion chart to compare one zeptohertz with other frequency measurement units.
| 0.001 aHz | 1.0E-19 cHz |
| 1.0E-20 dHz | 1.0E-22 daHz |
| 1.0E-39 EHz | 1.0E-6 fHz |
| 1.0E-30 GHz | 1.0E-21 Hz |
| 1.0E-24 kHz | 1.0E-27 MHz |
| 1.0E-15 µHz | 1.0E-18 mHz |
| 1.0E-12 nHz | 1.0E-36 PHz |
| 1.0E-9 pHz | 1.0E-33 THz |
| 1000 yHz | 1.0E-45 YHz |
| 1 zHz | 1.0E-42 ZHz |