ski / boot size
Ski Boot Size Calculator and Mondopoint Chart
Measure your foot in millimetres. Get Mondopoint, EU, US and UK, plus the sole length your bindings need.
What size ski boot do I need? Your ski boot size is your foot length. Mondopoint, the system alpine boots are sold in, is defined by ISO 9407:2019 as the length of the foot in millimetres, so a 280 mm (11 in) foot is Mondopoint 28.0 and there is nothing to convert. That is US men 10, US women 11, UK 9, and EU 43 1/3 in Tecnica's chart. A ski boot is fitted tighter than a shoe: Nordica publishes a performance fit a full size down, Mondopoint 27 for the same foot. Measure in the evening, in a ski sock, standing against a wall.
Ski Boot Size Chart: Mondopoint, EU, US and UK
Every row below is one foot length. The Mondopoint and millimetre columns are the same measurement written two ways. US and UK are arithmetic on it. EU is transcribed from Tecnica, because it does not follow a formula, and the last column is the sole length that goes into a binding.
| Mondo | mm | US men | US women | UK | EU Tecnica | EU Nordica | Sole mm |
|---|---|---|---|---|---|---|---|
| 22.0 | 220 | 4 | 5 | 3 | 35 1/2 | not published | 265 to 275 |
| 22.5 | 225 | 4.5 | 5.5 | 3.5 | 36 | 36 | 265 to 275 |
| 23.0 | 230 | 5 | 6 | 4 | 36 2/3 | 37 | 275 |
| 23.5 | 235 | 5.5 | 6.5 | 4.5 | 37 1/2 | 38 | 275 |
| 24.0 | 240 | 6 | 7 | 5 | 38 | 39 | 285 |
| 24.5 | 245 | 6.5 | 7.5 | 5.5 | 38 2/3 | 39 | 285 |
| 25.0 | 250 | 7 | 8 | 6 | 39 1/2 | 40 | 295 |
| 25.5 | 255 | 7.5 | 8.5 | 6.5 | 40 | 40-41 | 295 |
| 26.0 | 260 | 8 | 9 | 7 | 40 2/3 | 41 | 305 |
| 26.5 | 265 | 8.5 | 9.5 | 7.5 | 41 1/2 | 41-42 | 305 |
| 27.0 | 270 | 9 | 10 | 8 | 42 | 42 | 315 |
| 27.5 | 275 | 9.5 | 10.5 | 8.5 | 42 1/2 | 42-43 | 315 |
| 28.0 | 280 | 10 | 11 | 9 | 43 1/3 | 43 | 325 |
| 28.5 | 285 | 10.5 | 11.5 | 9.5 | 44 | 43-44 | 325 |
| 29.0 | 290 | 11 | 12 | 10 | 44 1/2 | 44 | 335 |
| 29.5 | 295 | 11.5 | 12.5 | 10.5 | 45 | 44-45 | 335 |
The chart stops where Tecnica's printed chart stops. Sizes outside it are real sizes; this page simply has no maker's EU figure for them and does not invent one. The two EU columns disagree on 13 of the 16 sizes both makers publish, which is the size of the gap between two brands on the same foot.
A Ski Boot Is Not Your Shoe Size
This is the part a size chart alone will not tell you. A street shoe has room at the end; a ski boot is fitted to the foot itself, because any space between your heel and the shell becomes movement, and movement becomes a bruised shin and a foot that will not steer the ski. Nordica puts a number on it: alongside every shoe size it prints two Mondopoint columns, a standard fit and a performance fit, 10 mm apart. A whole size. That is the maker saying, in its own chart, that a stiffer skier goes shorter.
Standing upright in a correctly sized boot your toes brush the front. Flex forward into it and they pull back off the end. If your toes are clear of the front while you stand, the shell is too long, whatever the chart says.
Width is the other axis, and it is not the same decision
Length gets you the shell; width, called the last, decides whether it fits. It is measured across the forefoot, and the makers band it differently: Atomic calls under 98 mm narrow, around 100 mm medium and 102 mm and above wide; Tecnica calls LV, 93 to 98 mm narrow, MV, 99 to 100 mm medium and HV, 103 mm wide. So a 100 mm last is medium to one of them and the top of medium to the other, which is why a shop measures your width rather than reading it off a table. A narrow foot in a wide shell has to be buckled down hard to feel secure, and that is the usual cause of ski boot pain.
How to measure your foot
Stand on a sheet of paper with your heel against a wall, wearing the ski sock you will ski in. Mark the end of the longest toe, which is not always the big one, and measure from the wall to the mark in millimetres. Do both feet and use the longer one. Do it in the evening, when your foot is at its largest, and stand up while you do it: a loaded foot is several millimetres longer than a lifted one.
How ski boot sizing works
Frequently asked questions
What size ski boot do I need for a 280 mm foot?
A 280 mm foot is Mondopoint 28.0, because Mondopoint is the foot length: 28.0 means 280 mm. That is US men 10, US women 11 and UK 9. Tecnica prints EU 43 1/3 for it and Nordica prints EU 43. A racer would take Mondopoint 27, one full size down, which is Nordica's own performance fit column rather than our advice.
Is Mondopoint the same as my foot length?
Yes, and that is the whole point of it. ISO 9407:2019 defines Mondopoint as foot length in millimetres, with linear foot width as a secondary measurement, graded in steps of 5 mm. So Mondopoint 26.5 is a 265 mm foot, and unlike a street shoe size there is nothing to convert and no brand interpretation in the number. What the boot then feels like still depends on its width and its shell, which is a separate axis.
Should a ski boot be the same size as my shoe?
No, and this is the mistake that ruins most first pairs. A ski boot is fitted to the foot, not to the shoe you wear over a sock with room to spare. Nordica publishes two Mondopoint columns for the same shoe size, a standard fit and a performance fit, and they are 10 mm apart: a full size. Your toes should brush the end when you stand upright and pull back when you flex forward into the boot. A boot that feels roomy in the shop is too big on the hill.
What is BSL and where do I find it?
Boot sole length, the outside length of the sole in millimetres, and it is the number a binding is adjusted to. It is printed on the heel or the side of the sole of every alpine boot. Tecnica publishes it beside each Mondopoint size: a 28 boot has a sole around 325 mm. Read yours off the boot rather than off a chart, then put it into the DIN calculator, because two boots at the same Mondopoint can differ by 10 mm of sole.
Why do two makers give different EU sizes for the same foot?
Because EU is not defined by the standard. ISO 9407:2019 covers foot length and width and nothing else, so each maker prints its own conversion. Tecnica and Nordica differ on 13 of the 16 sizes they both publish. US and UK are different: those really are arithmetic, and three makers agree on them row for row.
What ski boot width do I need?
Width, called the last, is measured across the forefoot and is a separate decision from length. The makers band it differently: Atomic calls under 98 mm narrow, around 100 mm medium and 102 mm and above wide; Tecnica calls LV, 93 to 98 mm narrow, MV, 99 to 100 mm medium and HV, 103 mm wide. A 100 mm last is therefore medium to one and the top of medium to the other. A narrow foot in a wide shell has to be clamped down to feel secure, which is what causes most boot pain.
Where these numbers come from
Mondopoint is a standard and the rest is not, so this page keeps the two apart. ISO 9407:2019, Footwear sizing, Mondopoint system of sizing and marking, defines foot length in millimetres, with linear foot width as a secondary measurement, graded in steps of 5 mm. It defines any conversion to European, United States or United Kingdom sizes. It is a paid document and nobody here has read the text: the scope quoted is from its public abstract.
The EU column is Tecnica's, transcribed from its Boot Sizer 2023/24, and the sole lengths are from the same sheet. The second EU column is Nordica's, from its Ski Boot Sizing Chart, shown because the two do not agree and a reader deserves to see that before trusting either. The two Mondopoint fits are Nordica's own columns. The width bands are Atomic and Tecnica, quoted as each publishes them.
The US and UK columns are arithmetic on the foot length, not a transcription, and they are the only columns three makers agree on. Nothing on this page is our own invention: where no maker publishes a figure, the cell says so instead of carrying a number.
Also useful: DIN setting calculator once you have your sole length, boot flex calculator for stiffness, and boot pain if the fit is already hurting.