Cm to Inches Converter
Convert centimeters to inches (and back) instantly — with the formula, a quick chart, and feet+inches breakdown.
Convert
Quick conversion chart
| cm | inches | ft + in |
|---|
The Formula: Divide by 2.54
That's the whole trick — one division. The number 2.54 isn't a measurement someone took; it's a definition. Since 1959, the international inch has been defined as exactly 2.54 centimeters, so this conversion has zero error by construction. Your answer is as precise as your input.
Quick Conversion Chart
| cm | inches | ft + in |
|---|---|---|
| 1 | 0.39 | 0 ft 0.39 in |
| 10 | 3.94 | 0 ft 3.94 in |
| 30 | 11.81 | 0 ft 11.81 in |
| 100 | 39.37 | 3 ft 3.37 in |
| 150 | 59.06 | 4 ft 11.06 in |
| 180 | 70.87 | 5 ft 10.87 in |
Worked Example: 180 cm
How tall is 180 cm in feet and inches?
Step 1: Convert to inches: 180 ÷ 2.54 = 70.87 in.
Step 2: Divide by 12 for feet: 70.87 ÷ 12 = 5.9058, so 5 full feet.
Step 3: Remainder in inches: 70.87 − 60 = 10.87 in.
Result: 5 ft 10.87 in — conventionally rounded to 5'11".
Reverse: Inches to Cm
Going the other way, multiply by 2.54: a 55-inch TV screen is 55 × 2.54 = 139.7 cm diagonally. Screen sizes, by the way, are always the diagonal — a "55-inch TV" is 55 inches corner to corner, not wide. Flip the direction toggle above to convert inches → cm freely.
Common Uses
- Height: medical forms, dating profiles, and sports stats often need both systems.
- DIY & sewing: patterns jump between cm and inches constantly — convert before you cut.
- Screen sizes: TVs and monitors are sold in inches worldwide, even in metric countries.
- Rainfall & snow: weather reports convert constantly for international audiences.
- Luggage: airlines quote size limits in both — 158 cm total is the common 62-inch limit.
Mental Math Shortcuts
For quick estimates without a calculator: divide cm by 2.5 instead of 2.54 (100 cm ≈ 40 in — close to the true 39.37). Or memorize that 30 cm ≈ 1 foot: 180 cm is six 30s, so about 6 feet — then adjust down slightly (5'11"). Going the other way, multiply inches by 2.5: 10 inches ≈ 25 cm (true: 25.4). These get you within 2% — fine for furniture, fabric, and guessing whether the shelf fits.
For heights specifically, there's an even faster trick: cm − 100, then divide the rest by 2.5, and that's roughly feet-and-inches math — or just remember benchmarks: 150 cm ≈ 4'11", 160 cm ≈ 5'3", 170 cm ≈ 5'7", 180 cm ≈ 5'11", 190 cm ≈ 6'3". Between benchmarks, every 2.5 cm is about an inch.
My saved numbers reuse them in any calculator
Save a number once — like your rent or hourly rate — then just type its name instead of the number, in any calculator here. You can also type formulas like 5000 * 1.1 right into any box.
Saved only in this browser — nothing is sent to us.
Frequently Asked Questions
How many inches are in 1 cm?
1 cm = 0.3937 inches (exactly 1 ÷ 2.54). So 10 cm ≈ 3.94 inches.
What is the formula for cm to inches?
inches = centimeters ÷ 2.54. Reverse: centimeters = inches × 2.54.
What is 180 cm in feet and inches?
180 cm = 70.87 inches = 5 feet 10.87 inches — commonly rounded to 5'11". Enter 180 above to see the breakdown.
Is 2.54 exact?
Yes. Since 1959, the inch has been defined as exactly 2.54 centimeters by international agreement — it is not a rounded approximation.
Why does the US still use inches?
Historical inertia and the cost of switching: construction, manufacturing and everyday habits are built around imperial units. The US officially adopted the metric system in 1975 but made conversion voluntary, so both systems coexist.