# 力单位转换器

> Convert kgf to newtons, lbf to N and kN to kgf or lbf, using standard gravity (9.80665 m/s²) and the exact pound-force of 4.4482216152605 N.

交互版本：https://www.calcopenly.com/zh/conversion/force-converter
主题：单位换算器

Every force unit is a fixed number of newtons, and one newton accelerates 1 kg at 1 m/s². The gravitational units use standard gravity, g₀ = 9.80665 m/s², set by the 3rd CGPM in 1901: a kilogram-force is 9.80665 N and a pound-force is 0.45359237 kg × 9.80665 m/s² = 4.4482216152605 N, both exact.

The default converts 1 kgf to 9.80665 N. Loads marked in kilograms-force or tonnes-force and climbing or lifting gear rated in kilonewtons are the usual reasons to convert: 1 kN is 101.97 kgf or 224.81 lbf.

A kilogram is a mass and a newton a force, so “1 kg = 9.81 N” holds only under standard gravity. Real gravity runs from about 9.78 m/s² at the equator to 9.83 m/s² at the poles, a spread of 0.5%.

## 输入

- **数值**: 输入源单位下的数值，也可以输入带有自身单位的数值
- **从** (选项：newton (N), kilonewton (kN), dyne (dyn), pound-force (lbf), kilogram-force (kgf), ounce-force (ozf), poundal (pdl))
- **到** (选项：newton (N), kilonewton (kN), dyne (dyn), pound-force (lbf), kilogram-force (kgf), ounce-force (ozf), poundal (pdl))

## 结果

- 转换后的数值 — 主要结果
- 换算
- 换算系数
- 精确性

## 公式

$$
\begin{gathered} x_{\text{to}} = x_{\text{from}} \times \dfrac{f_{\text{from}}}{f_{\text{to}}} \\ f = \text{one unit expressed in } \text{N} \end{gathered}
$$

## 计算示例

### 1 kgf in newtons

- 数值: 1 kgf
- 从: kilogram-force (kgf)
- 到: newton (N)
- **转换后的数值: 9.80665 N**
- 核验来源：1 kgf = 1 kg × 9.80665 m/s² (standard gravity, CGPM 1901)

### 1 lbf in newtons

- 数值: 1 lbf
- 从: pound-force (lbf)
- 到: newton (N)
- **转换后的数值: 4.44822161526 N**
- **精确性: 精确**
- 核验来源：0.45359237 kg × 9.80665 m/s² = 4.4482216152605 N (NIST SP 811 App. B)

### 1 kN in lbf

- 数值: 1 kN
- 从: kilonewton (kN)
- 到: pound-force (lbf)
- **转换后的数值: 224.8089431 lbf**
- 核验来源：1000 / 4.4482216152605 (Python 3.8 fractions from the legal definitions)

### 1 N in dynes

- 数值: 1 N
- 从: newton (N)
- 到: dyne (dyn)
- **转换后的数值: 100,000 dyn**
- 核验来源：1 dyn = 10⁻⁵ N (NIST SP 811 App. B)

## 常见问题

### How many newtons are in a kilogram?

A mass of 1 kg weighs 9.80665 N under standard gravity, which is the definition of 1 kilogram-force. The kilogram measures mass and the newton force, so the conversion needs an acceleration; 9.80665 m/s² is the conventional value fixed in 1901, and local gravity differs from it by up to about 0.3%.

### How do I convert lbf to newtons?

Multiply by 4.4482216152605, usually rounded to 4.448. One pound-force is the weight of one pound (0.45359237 kg) under standard gravity, so the factor is exact. A 200 lbf load is 889.64 N, and 1 N is 0.224809 lbf.

### How many kgf is 1 kN?

101.97 kgf. Multiply kilonewtons by 101.9716, or divide by 0.00980665, to get kilograms-force. A carabiner marked 22 kN is rated to 2,243 kgf, or 4,946 lbf, and a 5 kN anchor to 510 kgf. The factor is exact because the kilogram-force is defined with standard gravity, 9.80665 m/s².

### What is the difference between a pound and a pound-force?

A pound (lb) is mass, 0.45359237 kg; a pound-force (lbf) is the weight of that mass under standard gravity, 4.4482216152605 N. On Earth a 10 lb object weighs about 10 lbf, which is why everyday speech uses one word for both. The poundal, 0.138255 N, is the force that accelerates 1 lb at 1 ft/s².

### How many newtons does a person weigh?

A 70 kg person weighs 686.47 N under standard gravity (70 × 9.80665), which is 70 kgf or 154.3 lbf. Bathroom scales measure this force and divide by g to display kilograms, so a scale set up for standard gravity reads about 0.3% low at the equator and 0.3% high at the poles.

### “力单位转换器”有多准确？

准确性取决于输入值和方法的假设。十进制运算使用50位有效数字，但估算、数值方法和源数据的精度可能较低；显示时的舍入并不能消除这些限制。 已按独立来源核验的计算示例：4。 例如，“1 kgf in newtons”根据1 kgf = 1 kg × 9.80665 m/s² (standard gravity, CGPM 1901)进行核验。

### 这种方法出自哪里？

NIST SP 811 (2008), Guide for the Use of the SI, Appendix B — conversion factors; NIST Handbook 44, Appendix C — General tables of units of measurement.

## 来源

- [NIST SP 811 (2008), Guide for the Use of the SI, Appendix B — conversion factors](https://www.nist.gov/pml/special-publication-811)
- [NIST Handbook 44, Appendix C — General tables of units of measurement](https://www.nist.gov/pml/owm/nist-handbook-44-current-edition)