Kuoma size chart
Foot length + 15 mm = the inner length you need
Kuoma does not map sizes to foot lengths. They publish the inside length of every boot instead, which is more useful: measure the foot in the evening, add 15 mm for wool sock and growing room, and buy the size whose inner length clears that number.
A foot of 16.2 cm needs 177 mm, so size 27 (176 mm) is exactly on the line and 28 (183 mm) gives the full margin. Our own four-year-old wears the lined Kuoma 27 this winter, and it took the whole autumn sock drawer without complaint.
The width column is the quiet reason Kuomas feel roomy: 67 mm across at size 27 leaves space for a thick wool sock.
Inner measurements (Crosser, GT, Putkivarsi, Taika, Tarravarsi)
| EU | Inner length (mm) | Width (mm) |
|---|---|---|
| 20 | 129 | 57 |
| 21 | 135 | 59 |
| 22 | 142 | 61 |
| 23 | 149 | 62 |
| 24 | 155 | 63 |
| 25 | 162 | 64 |
| 26 | 169 | 66 |
| 27 | 176 | 67 |
| 28 | 183 | 68 |
| 29 | 189 | 70 |
| 30 | 196 | 72 |
| 31 | 203 | 73 |
| 32 | 209 | 74 |
| 33 | 216 | 76 |
| 34 | 223 | 77 |
| 35 | 227 | 79 |
| 36 | 230 | 82 |
| 37 | 237 | 83 |
| 38 | 244 | 85 |
| 39 | 250 | 86 |
Two quick answers
Do Kuoma boots run big?
They are cut wide, but the inner lengths are exact: measure the foot, add 15 mm, read the table. No size guessing needed.
Which Kuoma size for a 4-year-old?
Our measured example: a foot around 16 cm takes size 27 with a thin sock, 28 with the full wool-sock margin.
Source
Measurements from the manufacturer's own chart, checked August 10, 2026.