Length • NIST Exact

Inches Centimeters

in → cm

1 in = 2.54 cmNIST Exact

in → cm Reference Table

in cm
0.01 in 0.0254 cm
0.1 in 0.254 cm
0.5 in 1.27 cm
1 in 2.54 cm
2 in 5.08 cm
5 in 12.7 cm
10 in 25.4 cm
20 in 50.8 cm
50 in 127 cm
100 in 254 cm
500 in 1270 cm
1000 in 2540 cm

Values based on NIST SP 811 conversion factors

🌍 Real-World Examples

27-inch computer monitor

27 in = 68.58 cm

65-inch TV screen

65 in = 165.1 cm

14-inch laptop screen

14 in = 35.56 cm

Standard ruler length (12 inches)

12 in = 30.48 cm

Why Convert Inches to Centimeters?

Converting between inches (in) and centimeters (cm) is one of the most common length conversions. Whether for engineering, cooking, travel, or science, knowing how to quickly convert in to cm saves time and prevents errors.

Length conversions between in and cm are essential in international travel, construction, and sports. Airline carry-on luggage limits are typically defined in centimeters (55×40×20 cm), but US travelers think in inches. Architects and contractors regularly convert between metric and imperial measurements when working on international projects. In athletics, track distances may be in meters while road races use miles or kilometers.

How to Convert Inches to Centimeters

To convert inches to centimeters, use the following formula:

cm = in × 2.54

Example: 1 in = 2.54 cm

For example, 5 in = 12.7 cm, 10 in = 25.4 cm, and 100 in = 254 cm. Our calculator above performs this conversion instantly with full precision — no rounding errors.

Common Use Cases

  • 27-inch computer monitor: 27 in = 68.58 cm
  • 65-inch TV screen: 65 in = 165.1 cm
  • 14-inch laptop screen: 14 in = 35.56 cm
  • Standard ruler length (12 inches): 12 in = 30.48 cm

Common Mistakes to Avoid

  • Confusing similar units: Don't mix up meters (m) with miles (mi) — they differ by a factor of ~1600. Always check the unit symbol.
  • Rounding too early: When converting in to cm, carry at least 4 decimal places in intermediate calculations to avoid compounding errors.
  • Forgetting unit labels: Always write the unit symbol after the number. "5.5" is ambiguous — "5.5 cm" is clear.

Pro Tips

  • Memorize the factor: 1 in = 2.54 cm. For quick mental math, remember this base conversion.
  • Quick reference: 5 in = 12.7 cm · 10 in = 25.4 cm · 25 in = 63.5 cm · 50 in = 127 cm · 100 in = 254 cm
  • Bookmark this page: Save this converter for instant access. It works offline once loaded — no internet needed.

Inches to Centimeters Conversion Table

incm
0.01 in0.0254 cm
0.1 in0.254 cm
0.5 in1.27 cm
1 in2.54 cm
2 in5.08 cm
5 in12.7 cm
10 in25.4 cm
20 in50.8 cm
50 in127 cm
100 in254 cm
500 in1270 cm
1000 in2540 cm

All values in this table are mathematically exact per NIST SP 811.

Frequently Asked Questions

How many centimeters are in 1 inch?

1 in equals 2.54 cm. This is an exact conversion factor defined by NIST.

How do I convert inches to centimeters?

Multiply the value in in by the conversion factor. For example, 10 in = 25.4 cm. Use our calculator above for instant results.

Is the inches to centimeters conversion exact?

Yes, this conversion is mathematically exact based on the international definition of these units (NIST SP 811).

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