Conversion Result
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Inches (in)
About This Converter
- What it does
- Converts centimeters to decimal inches with inverse conversion.
- Input
- Length in centimeters (cm)
- Output
- Decimal inches; reverse cm value
- Formula
- inches = cm ÷ 2.54 (exact)
- Last updated
About Centimeters to Inches Conversion
Centimeters and inches are both used to measure short lengths, but they belong to different measurement systems — the metric system and the imperial system respectively. One inch equals exactly 2.54 centimeters by international definition. The conversion is widely needed in everyday life: clothing and shoe sizes, TV and monitor screen diagonals, and engineering drawings often require switching between the two units.
Conversion Formula
inches = cm ÷ 2.54
The exact relationship is 1 inch = 2.54 cm. To convert centimeters to inches, divide by 2.54. For the reverse (inches to cm), multiply by 2.54.
Worked Example
Convert 30 cm to inches: 30 ÷ 2.54 = 11.811 inches. Conversely, 11.811 × 2.54 = 30 cm exactly.
Common Use Cases
- Converting screen diagonal sizes — a 40 cm display equals about 15.75 inches
- Sewing and tailoring: European patterns give seam allowances in cm, while US patterns use inches
- Checking whether an imported item (photo frame, baking tin) fits a standard US shelf or oven
- Technical drawings: converting between ISO (metric) and ANSI (imperial) standards
- Comparing height measurements on international sizing charts for clothing
Frequently Asked Questions
1 centimeter = 0.393701 inches. This is an exact conversion: 1 inch = 2.54 cm, so 1 cm = 1 ÷ 2.54 ≈ 0.3937 in.
10 cm = 10 ÷ 2.54 = 3.937 inches, approximately 3 and 15/16 inches.
30 cm = 11.811 inches, approximately 11 and 13/16 inches — slightly less than 1 foot.
100 cm (1 meter) = 39.3701 inches, or 3 feet 3.37 inches.
1 inch = 2.54 cm exactly. This definition has been fixed internationally since 1959.
Yes. The international inch is defined as exactly 2.54 centimeters. This is not a rounded approximation — it is the exact legal definition in all major standards.
50 cm ÷ 2.54 = 19.685 inches, approximately 19 and 11/16 inches.
5 cm ÷ 2.54 = 1.9685 inches, approximately 2 inches.
Important Notes
- The conversion factor 1 in = 2.54 cm is exact, not rounded.
- Results are shown to 6 significant decimal places; round as needed.
- For compound feet-and-inches output, use the Centimeters to Feet & Inches converter.
- Zero and positive numbers only.