Zeptonewton is 1e-21 newton units.
Zeptonewtons to Kilogram-forces Converter — zN to kgf
Convert Zeptonewton (zN) to Kilogram-force (kgf) using the exact conversion factor (1 zeptonewton = 1.019716e-22 kilogram-force). See the formula, worked examples, conversion table, and common uses.
Zeptonewtons to Kilogram-forces 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.
Kilogram-force under standard gravity.
Result = input x 1e-21 / 9.80665.
Force units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Zeptonewtons to Kilogram-forces
Zeptonewton and Kilogram-force 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: Zeptonewton is 1e-21 newton units, and kilogram-force under standard gravity.
Formula
kilogram-forces = zeptonewtons × 1.019716e-22
This factor comes from each unit's defined relationship to the category's base unit: 1 zeptonewton equals 1e-21 base units, and 1 kilogram-force equals 9.80665 base units, so dividing one by the other gives the direct zeptonewton-to-kilogram-force factor of 1.019716e-22.
Simple example
1 zN × 1.019716e-22 = 1.019716e-22 kgf
1 zeptonewton = 1.019716e-22 kilogram-forces.
Real-world example
100 zN × 1.019716e-22 = 1.019716e-20 kgf
100 zeptonewtons = 1.019716e-20 kilogram-forces.
Conversion table
| Zeptonewton (zN) | Kilogram-force (kgf) |
|---|---|
| 1 zN | 1.019716e-22 kgf |
| 10 zN | 1.019716e-21 kgf |
| 50 zN | 5.098581e-21 kgf |
| 100 zN | 1.019716e-20 kgf |
| 500 zN | 5.098581e-20 kgf |
| 1,000 zN | 1.019716e-19 kgf |
Reverse conversion: Kilogram-force to Zeptonewton
1.019716e-22 kgf × 9.80665e+21 = 0.9999997911 zN
1.019716e-22 kilogram-forces = 0.9999997911 zeptonewtons.
zeptonewtons = kilogram-forces × 9.80665e+21
For a page dedicated to this direction, see Kilogram-force to Zeptonewton.
Understanding the Zeptonewton (zN)
Zeptonewton is 1e-21 newton units.
Understanding the Kilogram-force
Kilogram-force (kgf) measures force. Defined as the force exerted by standard gravity on a mass of one kilogram — exactly 9.80665 newtons. It is classified as a non-SI unit, deprecated but still encountered.
Where it's used: Still encountered in some older European and Asian engineering specifications and torque-related equipment, though official use has been phased out in favor of the newton
Kilogram-force vs. newton. The newton is the modern SI unit of force; kilogram-force is an older, gravity-dependent unit still occasionally seen on legacy equipment. 1 kgf equals exactly 9.80665 N.
Uses of the Kilogram-force today
- Appears on some older or legacy engineering and mechanical specifications, particularly torque wrenches and spring-force ratings, predating wider adoption of the newton
Kilogram-force — sources
- BIPM SI Brochure — Notes kilogram-force among non-SI force units whose use is discouraged in favor of the newton.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many kilogram-forces are in 1 zeptonewton?
1 zeptonewton equals 1.019716e-22 kilogram-forces, using the exact defined conversion factor rather than an estimate.
How do I convert zeptonewton to kilogram-force?
Multiply the zeptonewton value by 1.019716e-22. The converter above does this instantly to whatever precision you set.
How do I convert kilogram-force back to zeptonewton?
Use the reverse factor: 1 kilogram-force equals 9.80665e+21 zeptonewtons. You can also use the swap control in the converter above to flip the direction instantly.
What is a zeptonewton?
Zeptonewton (zN) is a unit of engineering.
What is a kilogram-force?
Kilogram-force (kgf) measures force. Defined as the force exerted by standard gravity on a mass of one kilogram — exactly 9.80665 newtons. It is classified as a non-SI unit, deprecated but still encountered.
Is the zeptonewton to kilogram-force conversion exact?
Yes. Defined as the force exerted by standard gravity on a mass of one kilogram — exactly 9.80665 newtons. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.
What is the difference between kilogram-force vs. newton?
The newton is the modern SI unit of force; kilogram-force is an older, gravity-dependent unit still occasionally seen on legacy equipment. 1 kgf equals exactly 9.80665 N.