Classic Clogs are "roomy fit" and come in whole sizes only. Half sizes should go down; a full size down works for many people. Lined and Bae/platform models fit snugger.
Crocs — Men
Crocs Men
US
UK
EU
CM
KR(mm)
6
5
38-39
24
240
7
6
39-40
25
250
8
7
41-42
26
260
9
8
42-43
27
270
10
9
43-44
28
280
11
10
45-46
29
290
12
11
46-47
30
300
13
12
48-49
31
310
Crocs — Women
Crocs Women
US
UK
EU
CM
KR(mm)
5
3
34-35
22
220
6
4
36-37
23
230
7
5
37-38
24
240
8
6
38-39
25
250
9
7
39-40
26
260
10
8
41-42
27
270
11
9
42-43
28
280
Crocs — Kids
Crocs Kids
US
UK
EU
CM
KR(mm)
C4
3
19-20
11.5
115
C5
4
20-21
12.5
125
C6
5
22-23
13.5
135
C7
6
23-24
14.5
145
C8
7
24-25
15.5
155
C9
8
25-26
16.5
165
C10
9
27-28
17.5
175
C11
10
28-29
18.5
185
C12
11
29-30
19.5
195
C13
12
30-31
20.5
205
J1
13
32-33
21
210
J2
1
33-34
22
220
J3
2
34-35
23
230
J4
3
36-37
24
240
Sizes are approximate and vary by brand
Tips
Crocs labels every product as Roomy, Relaxed or Standard fit; check it before applying the "size down" rule.
Men's and women's share the same shoe: M 7 = W 9 (a 2-size gap).
Kids run C (toddler) then J (junior). J4 ≈ women's 6, so older kids can buy adult sizes.