The watt (W) is the SI unit of power, equal to one joule of energy transferred per second.
Watts to Attowatts
Convert Watt (W) to Attowatt (aW) instantly with an exact formula, conversion table, and FAQ.
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Convert watts (W) to attowatts (aW) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
An Attowatt (aW) equals 1e-18 watt(s), a scaled unit of electrical power used for atto-scale electrical work.
aW = W × 1.000000e+18
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Formula
aW = W × 1.000000e+18
W = aW × 1.000000e-18
Conversion table
| 1 W | 1.000000e+18 aW |
| 5 W | 5.000000e+18 aW |
| 10 W | 1.000000e+19 aW |
| 20 W | 2.000000e+19 aW |
| 50 W | 5.000000e+19 aW |
| 100 W | 1.000000e+20 aW |
| 500 W | 5.000000e+20 aW |
| 1000 W | 1.000000e+21 aW |
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How the formula works
Both watt and attowatt measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in watts by 1.000000e+18 to get attowatts. To reverse the conversion, multiply a attowatt value by 1.000000e-18 to get back to watts.
Frequently asked questions
What is Watt (W)?
The watt (W) is the SI unit of power, equal to one joule of energy transferred per second.
What is Attowatt (aW)?
An Attowatt (aW) equals 1e-18 watt(s), a scaled unit of electrical power used for atto-scale electrical work.
How do I convert watts to attowatts?
Multiply the watt value by 1.000000e+18 to get the equivalent in attowatts. For example, 5 W × 1.000000e+18 = 5.000000e+18 aW.
Is this conversion exact?
Yes. Both units use fixed, defined scale factors, so the factor 1.000000e+18 is an exact, non-rounded value.
Can I convert attowatts back to watts?
Yes. Divide the attowatt value by 1.000000e+18, or multiply it by 1.000000e-18, to get watts.
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About converting watts to attowatts
The watt (W) is the SI unit of power, equal to one joule of energy transferred per second. An Attowatt (aW) equals 1e-18 watt(s), a scaled unit of electrical power used for atto-scale electrical work.
Use this calculator to move between watts and attowatts accurately for homework, engineering, billing, or everyday electricity calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.