Zeptohenry is 1e-21 henry units.
Zeptohenrys to Attohenrys Converter — zH to aH
Convert Zeptohenry (zH) to Attohenry (aH) using the exact conversion factor (1 zeptohenry = 0.001 attohenry). See the formula, worked examples, and conversion table.
Zeptohenrys to Attohenrys converter
Converter
Electricity Converter
Convert electrical units by family and calculate voltage, current, resistance, power, and energy with context values.
Context values
Some unit families need one extra value for a physically accurate result.
Attohenry is 1e-18 henry units.
Result = input x 1e-21 / 1e-18.
Electrical units in the same family convert directly.
Reserved above the conversion cards and below the converter.
About Converting Zeptohenrys to Attohenrys
Zeptohenry and Attohenry both belong to the electricity family — voltage, current, resistance, power, or energy — units that show up constantly when working across the different standards used by household wiring (120V/240V depending on region), automotive electrical systems (12V/24V), and electronics design. Specifically: Zeptohenry is 1e-21 henry units, and attohenry is 1e-18 henry units.
Formula
attohenrys = zeptohenrys × 0.001
This factor comes from each unit's defined relationship to the category's base unit: 1 zeptohenry equals 1e-21 base units, and 1 attohenry equals 1e-18 base units, so dividing one by the other gives the direct zeptohenry-to-attohenry factor of 0.001.
Simple example
1 zH × 0.001 = 0.001 aH
1 zeptohenry = 0.001 attohenrys.
Real-world example
120 zH × 0.001 = 0.12 aH
120 zeptohenrys = 0.12 attohenrys.
Conversion table
| Zeptohenry (zH) | Attohenry (aH) |
|---|---|
| 1 zH | 0.001 aH |
| 5 zH | 0.005 aH |
| 12 zH | 0.012 aH |
| 24 zH | 0.024 aH |
| 120 zH | 0.12 aH |
| 240 zH | 0.24 aH |
Reverse conversion: Attohenry to Zeptohenry
0.001 aH × 1000 = 1 zH
0.001 attohenrys = 1 zeptohenrys.
zeptohenrys = attohenrys × 1000
For a page dedicated to this direction, see Attohenry to Zeptohenry.
Understanding the Zeptohenry (zH)
Zeptohenry is 1e-21 henry units.
Understanding the Attohenry (aH)
Attohenry is 1e-18 henry units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many attohenrys are in 1 zeptohenry?
1 zeptohenry equals 0.001 attohenrys, using the exact defined conversion factor rather than an estimate.
How do I convert zeptohenry to attohenry?
Multiply the zeptohenry value by 0.001. The converter above does this instantly to whatever precision you set.
How do I convert attohenry back to zeptohenry?
Use the reverse factor: 1 attohenry equals 1,000 zeptohenrys. You can also use the swap control in the converter above to flip the direction instantly.
What is a zeptohenry?
Zeptohenry (zH) is a unit of electricity.
What is a attohenry?
Attohenry (aH) is a unit of electricity.
Is the zeptohenry to attohenry conversion exact?
Yes. Both zeptohenry and attohenry are defined by fixed standards rather than physical artifacts, so the factor of 0.001 used above is exact to as many digits as you choose to display.
What's the difference between voltage, current, and resistance?
Voltage (volts) is the electrical potential difference driving current through a circuit. Current (amperes) is the rate of flow of electric charge. Resistance (ohms) is how much a component opposes that flow. They're related by Ohm's law (V = I × R), but they are distinct physical quantities, and this page converts between units of just one of them.