Inches to CM Converter

How to convert inches to centimeters?

Converting inches to centimeters is essential for international shopping, DIY, clothing sizes, screen dimensions, and any project that mixes US and metric units. The conversion is simple and exact: multiply the inch value by 2.54 to get centimeters, since one inch equals exactly 2.54 cm by international agreement. Common references: 1 inch is 2.54 cm, 12 inches (one foot) is 30.48 cm, 24 inches is 60.96 cm, and 36 inches (one yard) is 91.44 cm. Our calculator gives decimal answers, full step-by-step formula, and a reference table for common values.

d_(cm) = d_(in) × 2.54

Example

Convert 10 inches to centimeters:

d_(cm) = 10in × 2.54 = 25.4cm

How many centimeters in an inch?

There are exactly 2.54 centimeters in one inch, a precise definition set by the 1959 International Yard and Pound Agreement. This makes the conversion completely deterministic with no rounding required at the factor level. So 1 inch is 2.54 cm, 2 inches is 5.08 cm, 5 inches is 12.7 cm, and 10 inches is 25.4 cm. Tape measures sold internationally often print both scales side by side, with the inch markings on one edge and the centimeter markings on the other for easy parallel reading.

How many inches in a centimeter?

There are approximately 0.393701 inches in one centimeter, the reciprocal of 2.54. So one centimeter is a bit less than half an inch, almost exactly 25/64 of an inch in fractional form. Quick mental conversions: 1 cm is roughly 0.4 inch, 5 cm is about 2 inches, 10 cm is just under 4 inches, and 30 cm (a school ruler) is almost exactly 12 inches (one foot). For precise scientific work, use the exact reciprocal rather than rounding the conversion factor.

What is the formula for inches to cm?

The formula is centimeters = inches multiplied by 2.54. So 10 inches times 2.54 equals 25.4 cm, and 100 inches equals 254 cm exactly. The reverse direction divides centimeters by 2.54 to get inches. Because 2.54 is an exact defined value rather than a measured approximation, this conversion preserves precision to whatever decimal accuracy your source measurement provides. Engineers, machinists, and scientists routinely chain this conversion into larger calculations without introducing additional rounding error.

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

First convert feet to inches (multiply by 12), add any extra inches, then multiply the total by 2.54. Example: 5 feet 7 inches equals 5 times 12 plus 7 equals 67 inches. Then 67 times 2.54 equals 170.18 cm. Quick reference: 5 feet is 152.4 cm, 5 feet 5 inches is 165.1 cm, 5 feet 9 inches is 175.3 cm, 6 feet is 182.9 cm, and 6 feet 3 inches is 190.5 cm. Most national ID and medical forms in the US still record height in inches, but international standards use centimeters.

Why convert inches to centimeters?

Most of the world uses the metric system, so converting inches to centimeters is constant for international shopping (clothing, shoes, electronics, furniture), import-export work, international research papers, and global manufacturing standards. American product specifications usually list inches, while imported items list cm or mm. Anyone ordering clothing from European or Asian retailers, comparing screen sizes across regions, or working with international engineering drawings needs this conversion. The exact 2.54 cm per inch ratio makes the math straightforward once memorized.

What is an inch?

The international inch is exactly 25.4 millimeters or 2.54 centimeters, fixed by the 1959 International Yard and Pound Agreement. There are 12 inches in a foot, 36 in a yard, and 63,360 in a mile. The word inch derives from Latin 'uncia' meaning one-twelfth (the inch was one-twelfth of a foot in ancient Rome). Today the inch is the dominant length unit in the US for personal measurements, paper sizes, screen diagonals, lumber, and clothing. The UK uses inches for similar everyday purposes alongside metric.

What is a centimeter?

A centimeter is one-hundredth of a meter, or 10 millimeters. The meter is the SI base unit of length, defined since 1983 as the distance light travels in vacuum in 1/299,792,458 second, making the centimeter precisely reproducible anywhere. Centimeters are the everyday metric length unit for human-scale objects: book sizes, monitor screens, body measurements, ruler markings, and most furniture dimensions. Smaller items use millimeters and larger items use meters, with the centimeter the sweet spot for typical household and personal use.

Popular inches to centimeters conversion table