**Diameter **and **circumference **defined by the formula **C = πd**, where **π** is equal to **3.14159**, our **diameter to circumference calculator** helps **convert** the **circumference** of a **circle** when given its **diameter**.

We have a

circlewith adiameterof10 units, we can use the calculator to find that itscircumferenceis approximately31.42 units.

## Diameter to Circumference Calculator

Inches Diameter to | Circumference (inches) |
---|---|

1 inch | 3.14 inches |

1.5 inches | 4.71 inches |

2 inches | 6.28 inches |

2.5 inches | 7.85 inches |

3 inches | 9.42 inches |

3.5 inches | 10.99 inches |

4 inches | 12.57 inches |

4.5 inches | 14.14 inches |

5 inches | 15.71 inches |

5.5 inches | 17.28 inches |

6 inches | 18.85 inches |

6.5 inches | 20.42 inches |

7 inches | 21.99 inches |

7.5 inches | 23.56 inches |

8 inches | 25.13 inches |

8.5 inches | 26.70 inches |

9 inches | 28.27 inches |

9.5 inches | 29.84 inches |

10 inches | 31.42 inches |

10.5 inches | 32.99 inches |

11 inches | 34.56 inches |

11.5 inches | 36.13 inches |

12 inches | 37.70 inches |

12.5 inches | 39.27 inches |

13 inches | 40.84 inches |

13.5 inches | 42.41 inches |

14 inches | 43.98 inches |

14.5 inches | 45.55 inches |

15 inches | 47.12 inches |

15.5 inches | 48.69 inches |

16 inches | 50.27 inches |

16.5 inches | 51.84 inches |

17 inches | 53.41 inches |

17.5 inches | 54.98 inches |

18 inches | 56.55 inches |

18.5 inches | 58.12 inches |

19 inches | 59.69 inches |

19.5 inches | 61.26 inches |

20 inches | 62.83 inches |

## Diameter to Circumference Chart

Diameter | Circumference |
---|---|

1 cm | 3.14 cm |

2 cm | 6.28 cm |

3 in | 9.42 in |

4 ft | 12.57 ft |

5 m | 15.71 m |

6 mm | 18.85 mm |

7 km | 21.99 km |

8 mi | 25.13 mi |

9 yd | 28.27 yd |

10 cm | 31.42 cm |

11 in | 34.56 in |

12 ft | 37.70 ft |

13 m | 40.84 m |

14 mm | 43.98 mm |

15 km | 47.12 km |

16 mi | 50.27 mi |

17 yd | 53.41 yd |

18 cm | 56.55 cm |

19 in | 59.69 in |

20 ft | 62.83 ft |

This chart provides comprehensive reference for converting between diameter and circumference for various units of measurement, including centimeters (**cm**), inches (**in**), feet (**ft**), meters (**m**), millimeters (**mm**), kilometers (**km**), miles (**mi**), and yards (**yd**).

## Diameter to Circumference Formula

The formula to calculate the **circumference** (C) of a **circle** from its **diameter** (d) is:

**C = πd**

`Where `**π (pi)** is approximately equal to **3.14159**.

For a **circle** with a **diameter** of **7 units**: C = π *7 ≈ **3.14159* 7 ≈ 21.99 units**

If the **diameter** is **15 cm**: C = π *15 ≈ **3.14159* 15 ≈ 47.12 cm**

## How do you convert diameter to circumference?

**Identify the diameter**: Measure or note the given**diameter**of the**circle**.**Multiply by π**: Multiply the**diameter**by**π**(**3.14159**).**Round if necessary**: Round the result to the desired number of**decimal places**.

Let’s convert a **diameter** of **12 inches** to **circumference**.

Diameter=12 inchesMultiply by

π:12 * 3.14159 = 37.69908 inchesRounding to two

decimal places:37.70 inches

The **circumference** of a **circle** with a **12-inch diameter** is approximately **37.70 inches**.

## Is diameter 2 times the circumference?

No, the **diameter** is **not** 2 times the **circumference**. In fact, it’s the **other way around**: the **circumference** is approximately **3.14159 (π)** times the **diameter**.

**Explanation**:

**Circumference**=**πd****Diameter**=**C / π**

If the **diameter** were 2 times the **circumference**, we would have: d = 2C

C = **πd** = **π(2C)** = **2πC**

This would imply that **π = 1/2**, which is **incorrect**. The actual value of **π** is approximately **3.14159**, not **0.5**.

## What is the circumference of a 20 inch diameter circle?

Rounded to two **decimal places**, the **circumference** is **62.83 inches**.

To find the **circumference** of a **20-inch diameter circle**:

- Use the formula:
**C = πd** - Plug in the values:
**C = π * 20** - Calculate:
**C ≈ 3.14159 * 20 ≈ 62.83 inches**

**Detailed calculation**: C = **3.14159265358979 * 20 = 62.8318530717959 inches**

## What is the circumference of a 5 ft diameter circle?

Rounded to two **decimal places**, the **circumference** is **15.71 feet**.

For a **circle** with a **5 ft diameter**:

- Apply the formula:
**C = πd** - Insert the values:
**C = π * 5 ft** - Compute:
**C ≈ 3.14159 * 5 ≈ 15.71 ft**

**Detailed calculation**: C = **3.14159265358979 * 5 = 15.7079632679489 ft**

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