电容是系统存储电荷的能力。它是在法拉德（F）中测量的。
1 J/F = 1,000,000,000,000,000,100,000 zF
1 zF = 1.0000e-21 J/F
例子:
将15 焦耳法拉德（Farad）转换为Zeptofarad：
15 J/F = 15,000,000,000,000,002,000,000 zF
| 焦耳法拉德（Farad） | Zeptofarad |
|---|---|
| 0.01 J/F | 10,000,000,000,000,002,000 zF |
| 0.1 J/F | 100,000,000,000,000,020,000 zF |
| 1 J/F | 1,000,000,000,000,000,100,000 zF |
| 2 J/F | 2,000,000,000,000,000,300,000 zF |
| 3 J/F | 3,000,000,000,000,000,500,000 zF |
| 5 J/F | 5,000,000,000,000,001,000,000 zF |
| 10 J/F | 10,000,000,000,000,002,000,000 zF |
| 20 J/F | 20,000,000,000,000,004,000,000 zF |
| 30 J/F | 30,000,000,000,000,004,000,000 zF |
| 40 J/F | 40,000,000,000,000,010,000,000 zF |
| 50 J/F | 50,000,000,000,000,004,000,000 zF |
| 60 J/F | 60,000,000,000,000,010,000,000 zF |
| 70 J/F | 70,000,000,000,000,010,000,000 zF |
| 80 J/F | 80,000,000,000,000,020,000,000 zF |
| 90 J/F | 90,000,000,000,000,010,000,000 zF |
| 100 J/F | 100,000,000,000,000,010,000,000 zF |
| 250 J/F | 250,000,000,000,000,030,000,000 zF |
| 500 J/F | 500,000,000,000,000,060,000,000 zF |
| 750 J/F | 750,000,000,000,000,100,000,000 zF |
| 1000 J/F | 1,000,000,000,000,000,100,000,000 zF |
| 10000 J/F | 10,000,000,000,000,000,000,000,000 zF |
| 100000 J/F | 100,000,000,000,000,000,000,000,000 zF |
规则