免费圆周长计算器
根据半径或直径快速计算圆的周长。
周长
43.9823
面积153.9380
直径14.0000
公式
## How to Calculate the Circumference of a Circle ### Formula **C = 2 × π × r** Or equivalently: **C = π × d** (where d is the diameter) Where: - **C** = Circumference - **π** ≈ 3.14159 - **r** = radius - **d** = diameter (2r)
计算示例
Find the circumference of a circle with radius 7.
- 01C = 2 × π × 7
- 02= 14π
- 03= 14 × 3.14159
- 04≈ 43.9823
常见问题
What is circumference?
Circumference is the distance around the edge of a circle — essentially the perimeter of a circle.
What is the relationship between circumference and diameter?
The circumference divided by the diameter always equals π (pi). This is actually the definition of pi: C/d = π.
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