40 cm is about 15.75 inches, or about 15 3/4 inch (slightly less). It is exactly 400 mm. Divide centimeters by 2.54, because 1 inch is defined as exactly 2.54 cm.
40 cm ≈ 15 3/4″
Slightly less than 15 3/4″ (by 0.05 mm) · ≈ 15.748 in
- Inches
- ≈ 15.748 in
- Nearest 1/16″
- 15 3/4″ 40 cm is 0.05 mm shorter
- Nearest 1/32″
- 15 3/4″ 40 cm is 0.05 mm shorter
- Nearest 1/64″
- 15 3/4″ 40 cm is 0.05 mm shorter
How long is 40 cm?
40 cm = 40 ÷ 2.54 in ≈ 15.7480 in. On a tape measure that is 15 3/4 in (15.75 in, 400.050 mm), and 40 cm is shorter than that by about 0.05 mm. In other units, 40 cm is exactly 400 mm and exactly 0.4 m, and ≈ 1.312 ft.
Numbers are hard to picture, so here is 40 cm drawn to scale next to real reference lengths.
Things that are about 40 cm long
Each size below comes from an official rule or a published specification. The note after each one says how close it is to 40 cm. Real objects vary.
A 40 cm ruler
A 40 cm rule is exactly this length, 40 cm (about 15.75 in).
A 16-inch measurement
16 in is exactly 40.64 cm, so it is 6.4 mm longer than 40 cm. A 16-inch pizza or laptop bag is sold under this nominal size.
An A3 sheet (long side)
A3 is 297 mm × 420 mm, so its long side is 42 cm, 2 cm longer than 40 cm.
A 40 × 60 cm frame
40 × 60 cm is a standard poster and frame size, so its short side is exactly 40 cm.
A 40 cm floor tile
Square floor tiles are sold as 40 × 40 cm, so each side is a nominal 40 cm.
40 cm to inches chart
Decimals are rounded to 3 places. In the fraction columns, + means the value is slightly longer than the fraction, − slightly shorter, and = exact.
| Centimeters (cm) | Inches (decimal) | Nearest 1/16″ | Nearest 1/32″ |
|---|---|---|---|
| 35 cm | 13.78 | 13 3/4″ + | 13 25/32″ − |
| 36 cm | 14.173 | 14 3/16″ − | 14 3/16″ − |
| 37 cm | 14.567 | 14 9/16″ + | 14 9/16″ + |
| 38 cm | 14.961 | 14 15/16″ + | 14 31/32″ − |
| 39 cm | 15.354 | 15 3/8″ − | 15 11/32″ + |
| 40 cm | 15.748 | 15 3/4″ − | 15 3/4″ − |
| 41 cm | 16.142 | 16 1/8″ + | 16 5/32″ − |
| 42 cm | 16.535 | 16 9/16″ − | 16 17/32″ + |
| 43 cm | 16.929 | 16 15/16″ − | 16 15/16″ − |
| 44 cm | 17.323 | 17 5/16″ + | 17 5/16″ + |
| 45 cm | 17.717 | 17 11/16″ + | 17 23/32″ − |
Frequently asked questions
How many inches is 40 cm?
40 cm is about 15.75 inches (15.7480 in), or about 15 3/4 inch.
How many mm is 40 cm?
40 cm is exactly 400 mm, because 1 cm is 10 mm.
Is 40 cm the same as 16 inches?
Almost. 16 inches is 40.64 cm, so 40 cm is 6.4 mm shorter than 16 inches.
How many feet is 40 cm?
40 cm is about 1.31 feet (1.3123 ft), or about 1 foot 3.75 inches.
How do I measure 40 cm without a ruler?
An A3 sheet is 42 cm on its long side, which is 2 cm over. Use a ruler when it matters.
How do I convert cm to inches?
Divide the centimeters by 2.54. For 40 cm, 40 ÷ 2.54 ≈ 15.75 inches.