Femtojoule is 1e-15 joule units.
Femtojoules to Microjoules Converter — fJ to uJ
Convert Femtojoule (fJ) to Microjoule (uJ) using the exact conversion factor (1 femtojoule = 1e-9 microjoule). See the formula, worked examples, and conversion table.
Femtojoules to Microjoules 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.
Microjoule is 0.000001 joule units.
Result = input x 1e-15 / 1e-6.
Energy units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Femtojoules to Microjoules
Femtojoule and Microjoule 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: Femtojoule is 1e-15 joule units, and microjoule is 0.000001 joule units.
Formula
microjoules = femtojoules × 1e-9
This factor comes from each unit's defined relationship to the category's base unit: 1 femtojoule equals 1e-15 base units, and 1 microjoule equals 0.000001 base units, so dividing one by the other gives the direct femtojoule-to-microjoule factor of 1e-9.
Simple example
1 fJ × 1e-9 = 1e-9 uJ
1 femtojoule = 1e-9 microjoules.
Real-world example
100 fJ × 1e-9 = 1e-7 uJ
100 femtojoules = 1e-7 microjoules.
Conversion table
| Femtojoule (fJ) | Microjoule (uJ) |
|---|---|
| 1 fJ | 1e-9 uJ |
| 10 fJ | 1e-8 uJ |
| 50 fJ | 5e-8 uJ |
| 100 fJ | 1e-7 uJ |
| 500 fJ | 5e-7 uJ |
| 1,000 fJ | 0.000001 uJ |
Reverse conversion: Microjoule to Femtojoule
1e-9 uJ × 1000000000 = 1 fJ
1e-9 microjoules = 1 femtojoule.
femtojoules = microjoules × 1000000000
For a page dedicated to this direction, see Microjoule to Femtojoule.
Understanding the Femtojoule (fJ)
Femtojoule is 1e-15 joule units.
Understanding the Microjoule (uJ)
Microjoule is 0.000001 joule units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many microjoules are in 1 femtojoule?
1 femtojoule equals 1e-9 microjoules, using the exact defined conversion factor rather than an estimate.
How do I convert femtojoule to microjoule?
Multiply the femtojoule value by 1e-9. The converter above does this instantly to whatever precision you set.
How do I convert microjoule back to femtojoule?
Use the reverse factor: 1 microjoule equals 1,000,000,000 femtojoules. You can also use the swap control in the converter above to flip the direction instantly.
What is a femtojoule?
Femtojoule (fJ) is a unit of engineering.
What is a microjoule?
Microjoule (uJ) is a unit of engineering.
Is the femtojoule to microjoule conversion exact?
Yes. Both femtojoule and microjoule are defined by fixed standards rather than physical artifacts, so the factor of 1e-9 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.