A Femtowatt (fW) equals 1e-15 watt(s), a scaled unit of electrical power used for femto-scale electrical work.
Femtowatts to Watts
Convert Femtowatt (fW) to Watt (W) instantly with an exact formula, conversion table, and FAQ.
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Convert femtowatts (fW) to watts (W) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
The watt (W) is the SI unit of power, equal to one joule of energy transferred per second.
W = fW × 1.000000e-15
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Formula
W = fW × 1.000000e-15
fW = W × 1.000000e+15
Conversion table
| 1 fW | 1.000000e-15 W |
| 5 fW | 5.000000e-15 W |
| 10 fW | 1.000000e-14 W |
| 20 fW | 2.000000e-14 W |
| 50 fW | 5.000000e-14 W |
| 100 fW | 1.000000e-13 W |
| 500 fW | 5.000000e-13 W |
| 1000 fW | 1.000000e-12 W |
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How the formula works
Both femtowatt and watt measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in femtowatts by 1.000000e-15 to get watts. To reverse the conversion, multiply a watt value by 1.000000e+15 to get back to femtowatts.
Frequently asked questions
What is Femtowatt (fW)?
A Femtowatt (fW) equals 1e-15 watt(s), a scaled unit of electrical power used for femto-scale electrical work.
What is Watt (W)?
The watt (W) is the SI unit of power, equal to one joule of energy transferred per second.
How do I convert femtowatts to watts?
Multiply the femtowatt value by 1.000000e-15 to get the equivalent in watts. For example, 5 fW × 1.000000e-15 = 5.000000e-15 W.
Is this conversion exact?
Yes. Both units use fixed, defined scale factors, so the factor 1.000000e-15 is an exact, non-rounded value.
Can I convert watts back to femtowatts?
Yes. Divide the watt value by 1.000000e-15, or multiply it by 1.000000e+15, to get femtowatts.
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About converting femtowatts to watts
A Femtowatt (fW) equals 1e-15 watt(s), a scaled unit of electrical power used for femto-scale electrical work. The watt (W) is the SI unit of power, equal to one joule of energy transferred per second.
Use this calculator to move between femtowatts and watts accurately for homework, engineering, billing, or everyday electricity calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.