Altra Size Chart
Altra makes road, trail, hiking and walking shoes built on its FootShape toe-box design, plus running apparel and accessories. Checked against Altra's own pages on 2026-10-24.
Altra official size charts
| US | UK | EU | CM |
|---|---|---|---|
| 4 | 3 | 37 | 22 |
| 4.5 | 3.5 | 37.5 | 22.5 |
| 5 | 4 | 38 | 23 |
| 5.5 | 4.5 | 38.5 | 23.5 |
| 6 | 5 | 39 | 24 |
| 6.5 | 5.5 | 39.5 | 24.5 |
| 7 | 6 | 40 | 25 |
| 7.5 | 6.5 | 40.5 | 25.5 |
| 8 | 7 | 41 | 26 |
| 8.5 | 7.5 | 42 | 26.5 |
| 9 | 8 | 42.5 | 27 |
| 9.5 | 8.5 | 43 | 27.5 |
| 10 | 9 | 44 | 28 |
| 10.5 | 9.5 | 44.5 | 28.5 |
| 11 | 10 | 45 | 29 |
| 11.5 | 10.5 | 46 | 29.5 |
| 12 | 11 | 46.5 | 30 |
| 12.5 | 11.5 | 47 | 30.5 |
| 13 | 12 | 48 | 31 |
| 14 | 13 | 49 | 32 |
| 15 | 14 | 50 | 33 |
| 16 | 15 | 51.5 | 34 |
Brand headers: U.S., U.K., E.U., CM. The page advises measuring your foot in centimetres and cross-referencing it with the chart.
Source: www.altrarunning.com/en-us/pages/size-chart
| US | UK | EU | CM |
|---|---|---|---|
| 4 | 2 | 34.5 | 20.5 |
| 4.5 | 2.5 | 35 | 21 |
| 5 | 3 | 35.5 | 21.5 |
| 5.5 | 3.5 | 36 | 22 |
| 6 | 4 | 37 | 22.5 |
| 6.5 | 4.5 | 37.5 | 23 |
| 7 | 5 | 38 | 23.5 |
| 7.5 | 5.5 | 38.5 | 24 |
| 8 | 6 | 39 | 24.5 |
| 8.5 | 6.5 | 40 | 25 |
| 9 | 7 | 40.5 | 25.5 |
| 9.5 | 7.5 | 41 | 26 |
| 10 | 8 | 42 | 26.5 |
| 10.5 | 8.5 | 42.5 | 27 |
| 11 | 9 | 43 | 27.5 |
| 11.5 | 9.5 | 44 | 28 |
| 12 | 10 | 44.5 | 28.5 |
| 13 | 11 | 46 | 29.5 |
Brand headers: U.S., U.K., E.U., CM. The page advises measuring your foot in centimetres and cross-referencing it with the chart.
Source: www.altrarunning.com/en-us/pages/size-chart
Key facts
- Altra's official men's chart: US 9 = UK 8 · EU 42.5 · CM 27.
- Altra's official women's chart: US 8 = UK 6 · EU 39 · CM 24.5.
- Altra's chart lists US men's 9 at 27 cm, within 2 mm of the median of 29 other brands whose charts also list the size in cm (27.0 cm). On paper it is sized like most of them.
- Altra lists no width options in its size guide.
- Source: Altra's official size guide, checked on 2026-10-24.
What Altra says about fit
- Measure your foot in centimetres before ordering, then use the chart to find your US, UK or EU size. (source)
- Every Altra shoe has a roomy FootShape toe box (not a wide shoe); styles come in Original (roomiest), Standard and Racing (snug midfoot) FootShape fits. (source)
- A few styles are offered in wide versions with a wider midfoot as well as the roomy toe box. (source)
How Altra compares with other brands
Altra's chart lists US men's 9 at 27 cm, within 2 mm of the median of 29 other brands whose charts also list the size in cm (27.0 cm). On paper it is sized like most of them.
Convert your Altra size to another brand
What we could not verify
- Altra's size chart lists no width options (such as D or 2E), so no widths are shown.
- Altra's size chart page has no kids' chart.
Questions
Which length does Altra's size chart list?
Altra's charts give these lengths — CM: size in cm, given by the brand as foot length. A measured foot length and a size in cm are about 8 mm apart for the same size, so compare your own foot length only with a column on the same scale.
Does the official chart tell me how a Altra shoe will fit?
Only in part. The chart gives the length each size is meant for; how a particular model fits also depends on its last, width and materials, which the chart does not show. Altra itself advises: Measure your foot in centimetres before ordering, then use the chart to find your US, UK or EU size. Every Altra shoe has a roomy FootShape toe box (not a wide shoe); styles come in Original (roomiest), Standard and Racing (snug midfoot) FootShape fits. A few styles are offered in wide versions with a wider midfoot as well as the roomy toe box.
When should I not compare Altra sizes with another brand?
When the two charts list different lengths. A measured foot length and a size in cm are about 8 mm apart, and the length of a foot is not the inside length of a shoe, so such a match can be half a size or more off. The converter matches only lengths on the same scale and lists the other brands separately.
When was Altra's chart last checked?
On 2026-10-24, against Altra's official size guide linked under each chart. The date changes only when the chart is checked again against the official page or its numbers change, not when this page's layout or wording changes.
Cite or reuse this data
Suggested citation: Sizelane, “Altra Size Chart”, https://sizelane.com/altra-size-chart (checked 2026-10-24).
The data is free to reuse under CC BY 4.0: name Sizelane, link to this page and keep the link to Altra's official source. Licence and update policy