Yoctowatt is 1e-24 watt units.
Yoctowatts to Zeptowatts Converter — yW to zW
Convert Yoctowatt (yW) to Zeptowatt (zW) using the exact conversion factor (1 yoctowatt = 0.001 zeptowatt). See the formula, worked examples, and conversion table.
Yoctowatts to Zeptowatts converter
Converter
Engineering Converter
Convert common stress, force, torque, power, and energy units used in engineering.
Context values
Some unit families need one extra value for a physically accurate result.
Zeptowatt is 1e-21 watt units.
Result = input x 1e-24 / 1e-21.
Power units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Yoctowatts to Zeptowatts
Yoctowatt and Zeptowatt both measure a quantity used in structural or mechanical engineering — commonly stress, pressure, force, torque, power, or energy — where converting between the unit conventions used in different regions, industries, or equipment specifications is a routine part of design work. Specifically: Yoctowatt is 1e-24 watt units, and zeptowatt is 1e-21 watt units.
Formula
zeptowatts = yoctowatts × 0.001
This factor comes from each unit's defined relationship to the category's base unit: 1 yoctowatt equals 1e-24 base units, and 1 zeptowatt equals 1e-21 base units, so dividing one by the other gives the direct yoctowatt-to-zeptowatt factor of 0.001.
Simple example
1 yW × 0.001 = 0.001 zW
1 yoctowatt = 0.001 zeptowatts.
Real-world example
100 yW × 0.001 = 0.1 zW
100 yoctowatts = 0.1 zeptowatts.
Conversion table
| Yoctowatt (yW) | Zeptowatt (zW) |
|---|---|
| 1 yW | 0.001 zW |
| 10 yW | 0.01 zW |
| 50 yW | 0.05 zW |
| 100 yW | 0.1 zW |
| 500 yW | 0.5 zW |
| 1,000 yW | 1 zW |
Reverse conversion: Zeptowatt to Yoctowatt
0.001 zW × 1000 = 1 yW
0.001 zeptowatts = 1 yoctowatt.
yoctowatts = zeptowatts × 1000
For a page dedicated to this direction, see Zeptowatt to Yoctowatt.
Understanding the Yoctowatt (yW)
Yoctowatt is 1e-24 watt units.
Understanding the Zeptowatt (zW)
Zeptowatt is 1e-21 watt units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many zeptowatts are in 1 yoctowatt?
1 yoctowatt equals 0.001 zeptowatts, using the exact defined conversion factor rather than an estimate.
How do I convert yoctowatt to zeptowatt?
Multiply the yoctowatt value by 0.001. The converter above does this instantly to whatever precision you set.
How do I convert zeptowatt back to yoctowatt?
Use the reverse factor: 1 zeptowatt equals 1,000 yoctowatts. You can also use the swap control in the converter above to flip the direction instantly.
What is a yoctowatt?
Yoctowatt (yW) is a unit of engineering.
What is a zeptowatt?
Zeptowatt (zW) is a unit of engineering.
Is the yoctowatt to zeptowatt conversion exact?
Yes. Both yoctowatt and zeptowatt 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.
Why do engineering unit conventions vary so much by region and industry?
Pressure, force, and stress can be expressed in metric (pascal, newton), US customary (psi, pound-force), or older and industry-specific units (atmosphere, torr, kip) depending on the country, industry, and even the equipment manufacturer, which is why engineers routinely need to convert between them when working across specs from different sources.