Inches to Centimeters: The American's Shopping & DIY Guide

Published on June 13, 2026 · 9 min read

You are buying a TV on a European website and the screen size is listed in centimeters. You are ordering furniture from IKEA and every measurement is in centimeters. You are checking a clothing size chart from a Korean brand and the chest measurement is in cm. For Americans, inches are instinctive — centimeters require a mental switch. This guide makes that switch automatic.

The Exact Formula

The international definition, adopted in 1959 and fixed by agreement:

1 inch = 2.54 centimeters (exact)

Centimeters = Inches × 2.54

Inches = Centimeters ÷ 2.54

This is one of the few perfectly exact metric-imperial conversions — 1 inch is defined as exactly 2.54 cm with no rounding. The number 2.54 is worth memorizing; it is the single most useful conversion factor for everyday American life.

Mental Math Shortcuts

Trick 1: Multiply by 2.5 (fast estimate)

Multiply inches by 2.5. Example: 12 inches × 2.5 = 30 cm. Exact: 30.48 cm. Error of 1.6% — perfect for shopping and furniture placement.

Trick 2: cm → inches (divide by 2.5)

Divide centimeters by 2.5 for approximate inches. Example: 100 cm ÷ 2.5 = 40 inches. Exact: 39.37 inches. Or just remember: 100 cm = 1 meter ≈ 39.4 inches ≈ 3 feet 3 inches.

Trick 3: Four anchor points to memorize

1 inch = 2.54 cm. 1 foot (12 in) = 30.48 cm. 1 yard (36 in) = 91.44 cm. 6 feet (72 in) = 182.88 cm. These four cover almost every everyday scenario.

Complete Reference Table: Inches to Centimeters

InchesCentimetersContext
¼"0.64 cmScrew head
½"1.27 cmSmall fitting
1"2.54 cmStandard reference
2"5.08 cmShort screw
3"7.62 cmPocket knife blade
4"10.16 cmSmartphone width
5"12.70 cmSmall phone screen
6"15.24 cmLarge phone / half foot
6.5"16.51 cmLarge phone screen
8"20.32 cmSmall tablet
10"25.40 cmTablet screen
12"30.48 cm1 foot / personal pizza
14"35.56 cmSmall laptop
15.6"39.62 cmStandard laptop
24"60.96 cmStandard monitor
27"68.58 cmLarge monitor
32"81.28 cmSmall TV
43"109.22 cmPopular TV size
55"139.70 cmMost popular US TV
65"165.10 cmXL TV
75"190.50 cmXXL TV

Height Chart: Feet & Inches to Centimeters

The most searched height conversions — for dating profiles, medical forms, and international job applications:

Feet & InchesTotal InchesCentimeters
5'0"60"152.4 cm
5'2"62"157.5 cm
5'4"64"162.6 cm
5'5"65"165.1 cm
5'6"66"167.6 cm
5'7"67"170.2 cm
5'8"68"172.7 cm
5'9"69"175.3 cm
5'10"70"177.8 cm
5'11"71"180.3 cm
6'0"72"182.9 cm
6'1"73"185.4 cm
6'2"74"187.9 cm
6'4"76"193.0 cm
6'6"78"198.1 cm

Men's Clothing: Waist Inches to CM and EU Sizes

US Waist (inches)CentimetersEU Size
28"71 cmEU 44
30"76 cmEU 46
32"81 cmEU 48
34"86 cmEU 50
36"91 cmEU 52
38"97 cmEU 54
40"102 cmEU 56
42"107 cmEU 58

IKEA Furniture: Centimeters to Feet

IKEA lists all dimensions in centimeters — even in US stores. Here are the most common dimensions translated:

IKEA cmInchesFeet
60 cm23.6"~2 ft
80 cm31.5"2 ft 7 in
100 cm39.4"3 ft 3 in
120 cm47.2"3 ft 11 in
140 cm55.1"4 ft 7 in
160 cm63.0"5 ft 3 in
180 cm70.9"5 ft 11 in
200 cm78.7"6 ft 7 in
240 cm94.5"7 ft 10 in

DIY: Lumber, Pipes and Hardware

American construction uses inches and feet. European hardware and metric tools use millimeters. Key facts every DIYer needs:

  • 1/4" (6.35 mm) — most common small bolt in US hardware stores
  • 1/2" (12.7 mm) — common pipe, bolt, and fitting size
  • 1" (25.4 mm) — exact reference; 25 mm metric is close but not identical
  • 2×4 lumber — actual size 1.5" × 3.5" (38 mm × 89 mm) — nominal name only
  • 4×8 plywood sheet — 48" × 96" = 121.9 cm × 243.8 cm
Important: Nominal US lumber sizes are not actual sizes. A "2×4" is actually 1.5" × 3.5". European lumber is sold by actual metric dimensions. This causes many failed projects when mixing materials from both systems.

Convert Any Length Instantly

For any length conversion — inches, centimeters, feet, meters, miles — use the ConvertProf Length Converter. Exact factors, no rounding, works offline.