20 cm at a glance
- Inches
- 7.8740 in
- Nearest 1/16 in
- 7 7/8 in
- Nearest 1/8 in
- 7 7/8 in
- Feet & inches
- 7.87 in (under 1 ft)
- Millimeters
- 200 mm
- Meters
- 0.2 m
How to convert 20 cm to inches
20 ÷ 2.54 = 7.874016 in
The inch has been defined as exactly 2.54 cm since 1959, so dividing by 2.54 is exact; the long decimal is just what that division produces. Multiplying by 0.3937 gives the same answer to four places.
Quick estimate
Multiply by 4 and divide by 10: 20 × 0.4 = 8 in. That overshoots by 0.13 in (about 1.6%) — fine for a rough check.
Reading 20 cm on an inch tape measure
US rulers mark fractions of an inch rather than decimals. Here is 7.8740 in rounded to each common mark, with the error that rounding introduces:
| Precision | Tape-measure reading | Error |
|---|---|---|
| 1/2 in | 8 in | +3.20 mm |
| 1/4 in | 7 3/4 in | −3.15 mm |
| 1/8 in | 7 7/8 in | +0.02 mm |
| 1/16 in | 7 7/8 in | +0.02 mm |
| 1/32 in | 7 7/8 in | +0.02 mm |
Things about 20 cm long
- 5% longer than a new, unsharpened pencil (about 7½ in), 19.05 cm (7.5 in).
- 5% shorter than the short side of an A4 sheet, 21 cm (8.27 in).
- 7% shorter than the short side of US letter paper, 21.59 cm (8.5 in).
- Photo sizes. 20 × 25 cm prints are the metric version of the 8 × 10 in print (20.32 × 25.4 cm).
- Carry-on bags. Most US airlines limit carry-ons to 22 × 14 × 9 in, about 56 × 36 × 23 cm, so 20 cm fits even the shortest side.
Centimeters near 20 cm
| Centimeters | Inches | Nearest 1/16 in |
|---|---|---|
| 15 cm | 5.9055 in | 5 7/8 in |
| 16 cm | 6.2992 in | 6 5/16 in |
| 17 cm | 6.6929 in | 6 11/16 in |
| 18 cm | 7.0866 in | 7 1/16 in |
| 19 cm | 7.4803 in | 7 1/2 in |
| 20 cm | 7.874 in | 7 7/8 in |
| 21 cm | 8.2677 in | 8 1/4 in |
| 22 cm | 8.6614 in | 8 11/16 in |
| 23 cm | 9.0551 in | 9 1/16 in |
| 24 cm | 9.4488 in | 9 7/16 in |
| 25 cm | 9.8425 in | 9 13/16 in |
Going the other way: 8 inches to cm is exactly 20.32 cm.
Frequently asked questions
How many inches is 20 cm?
20 cm is 7.87 inches (7.8740 to four places), found by dividing 20 by 2.54.
What is 20 cm in inches as a fraction?
To the nearest sixteenth, 20 cm is 7 7/8 in; to the nearest eighth it is 7 7/8 in.
Is 20 cm bigger than an inch?
Yes. 20 cm is 7.87 in, because one inch is only 2.54 cm.
How do I convert 20 cm to inches without a calculator?
Multiply by 0.4 for a quick estimate (8 in), then shave off about 1.6% to get close to the exact 7.87 in.