Home › Unit Converters › CM to MM Converter

CM to MM Converter

Enter any number of centimeters and the millimeters appear as you type. Press ⇄ to swap the direction, and see the step-by-step math under the result.

CentimetersFrom

MillimetersTo

Decimal places

Step-by-step calculation

How to use the CM to MM Converter

Type a value in the Centimeters box. The millimeters result appears instantly.
Going the other way? Type in the Millimeters box, or press the ⇄ swap button.
Set the precision with the decimal places menu.
Check the working in the step-by-step box, then press Copy result or click any row in the tables below.

Centimeters to millimeters formula

mm = cm × 10

Take the value in centimeters.
Multiply it by 10 (the number of millimeters in one centimeter).

Example: 10 cm × 10 = 100 mm.

Reverse formula (millimeters to centimeters): cm = mm ÷ 10. Example: 297 mm ÷ 10 = 29.7 cm.

The factor is a whole number (10), so this one is easy to do in your head.

cm to mm conversion table (1–100)

Click any row to load it into the converter.

Centimeters to millimeters

Centimeters	Millimeters
1 cm	10 mm
2 cm	20 mm
3 cm	30 mm
4 cm	40 mm
5 cm	50 mm
6 cm	60 mm
7 cm	70 mm
8 cm	80 mm
9 cm	90 mm
10 cm	100 mm
11 cm	110 mm
12 cm	120 mm
13 cm	130 mm
14 cm	140 mm
15 cm	150 mm
16 cm	160 mm
17 cm	170 mm
18 cm	180 mm
19 cm	190 mm
20 cm	200 mm
21 cm	210 mm
22 cm	220 mm
23 cm	230 mm
24 cm	240 mm
25 cm	250 mm
26 cm	260 mm
27 cm	270 mm
28 cm	280 mm
29 cm	290 mm
30 cm	300 mm
31 cm	310 mm
32 cm	320 mm
33 cm	330 mm
34 cm	340 mm
35 cm	350 mm
36 cm	360 mm
37 cm	370 mm
38 cm	380 mm
39 cm	390 mm
40 cm	400 mm
41 cm	410 mm
42 cm	420 mm
43 cm	430 mm
44 cm	440 mm
45 cm	450 mm
46 cm	460 mm
47 cm	470 mm
48 cm	480 mm
49 cm	490 mm
50 cm	500 mm
51 cm	510 mm
52 cm	520 mm
53 cm	530 mm
54 cm	540 mm
55 cm	550 mm
56 cm	560 mm
57 cm	570 mm
58 cm	580 mm
59 cm	590 mm
60 cm	600 mm
61 cm	610 mm
62 cm	620 mm
63 cm	630 mm
64 cm	640 mm
65 cm	650 mm
66 cm	660 mm
67 cm	670 mm
68 cm	680 mm
69 cm	690 mm
70 cm	700 mm
71 cm	710 mm
72 cm	720 mm
73 cm	730 mm
74 cm	740 mm
75 cm	750 mm
76 cm	760 mm
77 cm	770 mm
78 cm	780 mm
79 cm	790 mm
80 cm	800 mm
81 cm	810 mm
82 cm	820 mm
83 cm	830 mm
84 cm	840 mm
85 cm	850 mm
86 cm	860 mm
87 cm	870 mm
88 cm	880 mm
89 cm	890 mm
90 cm	900 mm
91 cm	910 mm
92 cm	920 mm
93 cm	930 mm
94 cm	940 mm
95 cm	950 mm
96 cm	960 mm
97 cm	970 mm
98 cm	980 mm
99 cm	990 mm
100 cm	1,000 mm

Millimeters to centimeters

Millimeters	Centimeters
1 mm	0.1 cm
2 mm	0.2 cm
3 mm	0.3 cm
4 mm	0.4 cm
5 mm	0.5 cm
6 mm	0.6 cm
7 mm	0.7 cm
8 mm	0.8 cm
9 mm	0.9 cm
10 mm	1 cm
11 mm	1.1 cm
12 mm	1.2 cm
13 mm	1.3 cm
14 mm	1.4 cm
15 mm	1.5 cm
16 mm	1.6 cm
17 mm	1.7 cm
18 mm	1.8 cm
19 mm	1.9 cm
20 mm	2 cm
21 mm	2.1 cm
22 mm	2.2 cm
23 mm	2.3 cm
24 mm	2.4 cm
25 mm	2.5 cm
26 mm	2.6 cm
27 mm	2.7 cm
28 mm	2.8 cm
29 mm	2.9 cm
30 mm	3 cm
31 mm	3.1 cm
32 mm	3.2 cm
33 mm	3.3 cm
34 mm	3.4 cm
35 mm	3.5 cm
36 mm	3.6 cm
37 mm	3.7 cm
38 mm	3.8 cm
39 mm	3.9 cm
40 mm	4 cm
41 mm	4.1 cm
42 mm	4.2 cm
43 mm	4.3 cm
44 mm	4.4 cm
45 mm	4.5 cm
46 mm	4.6 cm
47 mm	4.7 cm
48 mm	4.8 cm
49 mm	4.9 cm
50 mm	5 cm
51 mm	5.1 cm
52 mm	5.2 cm
53 mm	5.3 cm
54 mm	5.4 cm
55 mm	5.5 cm
56 mm	5.6 cm
57 mm	5.7 cm
58 mm	5.8 cm
59 mm	5.9 cm
60 mm	6 cm
61 mm	6.1 cm
62 mm	6.2 cm
63 mm	6.3 cm
64 mm	6.4 cm
65 mm	6.5 cm
66 mm	6.6 cm
67 mm	6.7 cm
68 mm	6.8 cm
69 mm	6.9 cm
70 mm	7 cm
71 mm	7.1 cm
72 mm	7.2 cm
73 mm	7.3 cm
74 mm	7.4 cm
75 mm	7.5 cm
76 mm	7.6 cm
77 mm	7.7 cm
78 mm	7.8 cm
79 mm	7.9 cm
80 mm	8 cm
81 mm	8.1 cm
82 mm	8.2 cm
83 mm	8.3 cm
84 mm	8.4 cm
85 mm	8.5 cm
86 mm	8.6 cm
87 mm	8.7 cm
88 mm	8.8 cm
89 mm	8.9 cm
90 mm	9 cm
91 mm	9.1 cm
92 mm	9.2 cm
93 mm	9.3 cm
94 mm	9.4 cm
95 mm	9.5 cm
96 mm	9.6 cm
97 mm	9.7 cm
98 mm	9.8 cm
99 mm	9.9 cm
100 mm	10 cm

Common values

Centimeters	Millimeters	Example
1 cm	10 mm	1 cm
2.54 cm	25.4 mm	1 inch
5 cm	50 mm	5 cm
10 cm	100 mm	10 cm
15 cm	150 mm	15 cm
21 cm	210 mm	A4 width (21 cm)
29.7 cm	297 mm	A4 height
30 cm	300 mm	About a ruler
50 cm	500 mm	50 cm
100 cm	1,000 mm	1 meter

About centimeters and millimeters

Centimeters (cm). The centimeter is one hundredth of a meter (10 millimeters). It is the everyday metric unit for body height, clothing and short lengths.

Millimeters (mm). The millimeter is one thousandth of a meter. It is used for small, precise measurements such as screws, rainfall, paper and engineering drawings.

Frequently asked questions

How many millimeters in 1 centimeter?

One centimeter equals 10 millimeters.

How do you convert centimeters to millimeters?

Multiply the number of centimeters by 10. For example, 10 cm × 10 = 100 mm.

What is 29.7 centimeters in millimeters?

29.7 cm is 297 mm (a4 height).

How do I convert millimeters back to centimeters?

Divide by 10, or press the ⇄ swap button above. For example, 297 mm ÷ 10 = 29.7 cm.

Why are metric conversions so simple?

Metric length units are powers of ten apart: 10 mm = 1 cm, 100 cm = 1 m and 1,000 m = 1 km. Converting only moves the decimal point.

Is this converter free and private?

Yes. It is free with no sign-up, and every calculation runs in your browser, so nothing you type is sent to a server.

Related tools