Converting between centimeters (cm) and inches is one of the most common everyday math tasks. Whether you’re shopping for furniture online, measuring your height, or following a DIY tutorial, knowing how to switch between cm to inches and inches to cm saves time and avoids mistakes.
This guide will walk you through formulas, conversion charts, examples, real-life applications, and FAQs. By the end, you’ll never wonder again: “How do I convert inch to cm or cm to inch?”
Why CM to Inches Conversion Matters
The metric system (centimeters, meters) is used globally, while the imperial system (inches, feet) dominates in the United States. Because of this split:
- Online stores list sizes in cm and inches.
- International travel or clothing purchases often require inches to cm conversion.
- Engineering, design, and science projects frequently switch between the two.
Understanding the conversion ensures accuracy whether you’re ordering a 40 cm monitor or a 15-inch laptop.
The Exact Conversion Formula
1 inch = 2.54 centimeters (exact value)
1 cm = 0.3937 inches (approximate)
Formula to Convert Inches to CM:
cm = inches × 2.54
Formula to Convert CM to Inches:
inches = cm ÷ 2.54
Quick Reference Conversion Table
| Inches | Centimeters |
|---|---|
| 1 in | 2.54 cm |
| 5 in | 12.7 cm |
| 10 in | 25.4 cm |
| 20 in | 50.8 cm |
| 30 in | 76.2 cm |
| 40 in | 101.6 cm |
| Centimeters | Inches |
|---|---|
| 1 cm | 0.39 in |
| 5 cm | 1.97 in |
| 10 cm | 3.94 in |
| 20 cm | 7.87 in |
| 50 cm | 19.69 in |
| 100 cm | 39.37 in |
Real-Life Conversion Examples
Example 1: Height
A person is 170 cm tall.
170 ÷ 2.54 = 66.9 inches ≈ 5’7”.
Example 2: Screen Size
A monitor measures 24 inches.
24 × 2.54 = 60.96 cm.
Example 3: DIY Project
A board length is 200 cm.
200 ÷ 2.54 = 78.74 inches.
Differences: CM vs. Inch
| Feature | Centimeters (cm) | Inches (in) |
|---|---|---|
| System | Metric | Imperial |
| Base Unit Relation | 100 cm = 1 m | 12 in = 1 ft |
| Popular Usage | Worldwide | USA, UK (partly) |
| Everyday Example | Clothing, science | TV sizes, height |
SEO-Targeted Sections
CM to Inches
A 76 cm waist equals about 29.9 inches. Divide cm by 2.54.
Inches to CM
A 12-inch tablet equals 30.48 cm. Multiply inches by 2.54.
Inch to CM
1 inch = 2.54 cm. For example, 8.5 in paper width = 21.59 cm.
CM to Inch
1 cm = 0.3937 inches. Example: 30 cm = 11.81 inches.
Practical Applications
- Clothing: Waistbands and dress lengths vary between cm and inches.
- Technology: TVs, monitors, and smartphones listed in inches often need cm conversions.
- DIY Projects: Wood, tiles, curtains, and furniture require accurate measurement conversions.
- Travel: Luggage often listed in both cm and inches.
- Sports: Equipment sizes in inches or cm depending on region.
FAQs About CM to Inches Conversion
1. How many cm in 1 inch?
1 inch = 2.54 cm.
2. How many inches in 1 cm?
1 cm ≈ 0.3937 inches.
3. How do I convert cm to inches quickly?
Divide the cm value by 2.54.
4. How do I convert inches to cm quickly?
Multiply the inch value by 2.54.
5. Why do we use inches in the US?
Because the imperial system is still widely used in daily life, while the metric system is global.
