Inches to Centimeters

About Inches to Cm Conversion

The inch-to-centimeter conversion is one of the most commonly needed unit conversions. Whether you're shopping for a TV, checking product dimensions, or comparing measurements across different countries, knowing how to convert between these units is essential.

The Conversion Factor

One inch equals exactly 2.54 centimeters. This is not an approximation — it's the exact definition established by international agreement in 1959. This precision means every conversion is mathematically accurate.

Why This Conversion Matters

• Screen sizes — TVs, monitors, phones, and tablets are typically measured in inches (32", 55", 65"), but you may need cm to visualize the actual size
• Online shopping — Products from the US often list dimensions in inches, while you may think in centimeters
• Body measurements — Converting height or clothing sizes between imperial and metric systems
• DIY and construction — Working with tools and materials from different measurement systems

Quick Mental Math

For rough estimates: multiply inches by 2.5 for a quick approximation. For example, 10 inches ≈ 25 cm (exact: 25.4 cm). This gets you within 2% of the accurate value.

How to Convert Inches to Cm

Using This Tool

1. Enter your value in inches in the top input field
2. See the cm result appear instantly in the bottom field
3. Copy either value using the copy buttons

The tool works both ways — you can also enter a cm value in the bottom field to convert it to inches.

Swap Direction

Click the swap button (circular arrow icon) between the two fields to exchange the values. This is useful when you want to quickly switch between converting inches→cm and cm→inches.

The Formula

The mathematical formula is straightforward:

• Inches to cm: cm = inches × 2.54
• Cm to inches: inches = cm ÷ 2.54

Common Conversions Reference

The Quick Reference section shows commonly needed conversions at a glance. These include popular screen sizes (24", 32", 55", 65") and other frequently converted values.

Features

Two-Way Conversion

Convert in either direction. Enter inches to get cm, or enter cm to get inches. Both input fields are active and update the other in real-time.

Instant Results

No buttons to click, no waiting. Results appear as you type, making it fast to try different values.

Swap Function

Quickly swap the values between the two fields. Perfect when you need to reverse your conversion or try the opposite direction.

Quick Reference Table

See common conversions at a glance without calculating. Includes popular screen sizes and frequently needed values.

One-Click Copy

Copy either the inches or cm value to your clipboard with a single click. Values are copied without formatting for easy pasting.

Privacy

All calculations happen in your browser:

• No server requests — Values never leave your device
• No tracking — We don't collect conversion data
• Works offline — Once loaded, no internet needed

Frequently Asked Questions

How many cm is 1 inch?

1 inch equals exactly 2.54 centimeters. This is the internationally agreed definition of the inch since 1959.

How do I convert inches to cm manually?

Multiply the number of inches by 2.54. For example: 10 inches × 2.54 = 25.4 cm.

Why are TV screens measured in inches?

Screen sizes are measured diagonally in inches because the US television industry set this standard, and it became the global convention. A "55-inch TV" means the diagonal measurement from corner to corner is 55 inches (139.7 cm).

What's the difference between inch and cm?

The inch is an imperial unit used mainly in the United States, United Kingdom (partially), and Canada (partially). The centimeter is a metric unit used by most of the world. The metric system is based on powers of 10, making calculations simpler.

Is 2.54 cm per inch exact?

Yes. Since 1959, the inch has been defined as exactly 25.4 millimeters (2.54 cm). This is not an approximation or rounded figure — it's the official definition.

How accurate is this converter?

The converter uses the exact 2.54 conversion factor and JavaScript's floating-point precision (about 15-17 significant digits). Results are displayed with up to 8 decimal places.