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Centimeters to Inches Calculator | Convert CM to Inches Instantly

Convert centimeters to inches instantly with our free online calculator. 1 cm = 0.3937 inches. Includes handy conversion chart for height and screen sizes.

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Purpose

Need to convert centimeters to inches? Whether you're measuring your height for a US driver's license, shopping for a TV, or working on a DIY project, this calculator gives you accurate conversions instantly.

The Formula: 1 centimeter equals approximately 0.3937 inches. This relationship is defined by the international inch, which was standardized in 1959 as exactly 2.54 centimeters.

The metric system (centimeters) is used in most countries worldwide, while the imperial system (inches) remains common in the United States for everyday measurements like height, screen sizes, and construction materials.

How to use

How to Convert CM to Inches

  1. Enter your measurement in centimeters in the input field above
  2. View your result instantly displayed in inches
  3. Copy or use the converted value for your needs

Common Conversion Reference

Centimeters Inches Common Use
2.54 cm 1 inch Standard reference
30.48 cm 12 inches (1 foot) Ruler length
91.44 cm 36 inches (1 yard) Fabric measurements
152.4 cm 60 inches (5 feet) Average height
182.88 cm 72 inches (6 feet) Tall height

Pro Tip: For quick mental math, remember that 1 inch is roughly 2.5 cm, so divide your centimeters by 2.5 for a quick estimate.

Examples

Real-World Conversion Examples

Example 1: Converting Height (170 cm)

A person who is 170 cm tall:

170 cm × 0.393701 = 66.93 inches
66.93 ÷ 12 = 5 feet 6.93 inches ≈ 5'7"

Example 2: TV Screen Size (140 cm diagonal)

A TV advertised as 140 cm diagonal:

140 cm × 0.393701 = 55.12 inches

This is approximately a 55-inch TV.

Example 3: Furniture Width (80 cm)

A desk that's 80 cm wide:

80 cm × 0.393701 = 31.50 inches

About 2 feet 7.5 inches wide.

Example 4: Phone Screen (16.5 cm)

A smartphone screen measuring 16.5 cm diagonally:

16.5 cm × 0.393701 = 6.5 inches

How it works

The Conversion Formula

Inches = Centimeters × 0.393701

Or equivalently:

Inches = Centimeters ÷ 2.54

Why This Number?

The conversion factor comes from the international agreement in 1959 that defined:

  • 1 inch = exactly 2.54 centimeters
  • 1 centimeter = 1/2.54 inches ≈ 0.393701 inches

This definition is used worldwide and is the basis for all metric-imperial length conversions.

Manual Calculation Example

To convert 170 cm to inches:

170 cm ÷ 2.54 = 66.93 inches

Or: 170 × 0.393701 = 66.93 inches

FAQ

How do I convert cm to inches?

To convert centimeters to inches, multiply your centimeter value by 0.393701, or divide by 2.54. For example, 100 cm × 0.393701 = 39.37 inches. The division method (÷ 2.54) is often easier for mental math since 2.54 is the exact number of centimeters in one inch.

How many inches is 1 cm?

One centimeter equals exactly 0.393701 inches, or approximately 0.4 inches. This is because 1 inch is defined as exactly 2.54 centimeters, making 1 cm equal to 1/2.54 inches. For quick estimates, you can think of 1 cm as being slightly less than half an inch.

How do I convert my height from cm to feet and inches?

First, convert your height to inches by multiplying by 0.393701 (or dividing by 2.54). Then divide by 12 to get feet, and the remainder is inches. For example, 175 cm ÷ 2.54 = 68.9 inches. 68.9 ÷ 12 = 5 feet with 8.9 inches remaining, so 175 cm = 5'9".

What is 150 cm in inches?

150 centimeters equals 59.06 inches, which is approximately 4 feet 11 inches. This is calculated by multiplying 150 by 0.393701 or dividing 150 by 2.54.

Why do some countries use centimeters and others use inches?

Most countries use the metric system (centimeters, meters) because it's based on powers of 10, making calculations simpler. The United States, along with Liberia and Myanmar, still primarily uses imperial units (inches, feet) for everyday measurements due to historical reasons and the cost of switching systems.

Is the cm to inches conversion exact?

Yes, the conversion is mathematically exact. Since 1959, the international inch has been defined as exactly 2.54 centimeters. This means 1 cm = 1/2.54 inches = 0.393700787... inches. Our calculator uses sufficient precision for all practical purposes.