Altra Shoe Size Chart

Altra's own published size chart, covering a 22cm to 34cm foot, with 2 real width fittings rather than length alone, including a children's chart Altra publishes itself. Every figure below is keyed to a measured foot length rather than converted from another size number. Open the calculator with Altra selected to read it against all 35 brands at once.

Does Altra run small?

For women's sizes, yes. By its own size chart, Altra is in line with most brands in men's sizes and runs about half a size small in women's sizes. A 24 cm foot is a women's US 7 in 16 of 34 other brands' charts, and a US 7.5 in Altra. Charts show how a brand means its sizes to fit, not how any one shoe feels, so read Altra's own fit advice below as well.

How this is worked out: every foot length from 25 to 29 cm (men's) and 22.5 to 26 cm (women's), in 1 mm steps, is read against Altra's chart and the other 34 brands' charts the way the calculator reads them, rounding up between sizes. The answer is the average gap between Altra's size and the size the other brands give most often. See the methodology.

Altra men's size chart

Altra women's size chart

Altra kids' size chart

Altra width chart

Altra publishes 2 men's and 2 women's width fittings. The standard fitting is D in men's and B in women's, so a D is the standard men's fitting but a wider women's one. Check which chart a letter belongs to before carrying it across.

Men's fittings

Women's fittings

Not every model is made in every fitting. Enter a forefoot width in the calculator and it returns Altra's own fitting for your foot. The width chart compares fittings across brands, and the wide-feet guide shows how to tell whether your foot is wide.

How to measure for Altra

Measure heel-to-toe standing, using the longer foot. IMPORTANT -- Altra's own sizing instructions tell you to ADD 0.5cm to your measured foot length before reading their chart, to allow room for your toes to splay in their wider FootShape toe box. The figures here are Altra's published chart values as-is, so if you want to follow Altra's own guidance, add 0.5cm to your measurement before entering it, or simply take the next half size up from the result shown.

Altra fit guidance

Altra is built around two features that set it apart: a zero-drop platform (heel and forefoot at the same height) and a foot-shaped 'FootShape' toe box that is noticeably wider at the toes than a conventional last. If you are coming from a traditional running shoe, the extra toe room is normal and intended, not a sign the shoe is too big -- but see the measurement note above about Altra's own recommendation to allow an extra 0.5cm. Altra's youth range runs roughly a 19cm to 24.5cm foot. Two quirks in Altra's own published youth chart are worth knowing: it lists both a 3.5 and a 4 at 22.5cm, so those two sizes are the same length in their table, and its EU column runs out of sequence at US 2, so that EU value is omitted here rather than guessed. Note also that Altra's adult advice to add 0.5cm before reading the chart is not repeated on their youth chart. Altra offers a standard and one wide fitting on many models. The wide is designated 2E in men's and D in women's. Altra often labels the standard simply 'Standard' or 'R' rather than D, so a listing without a width letter is the standard. Bear in mind Altra's FootShape standard is already wider through the toes than most brands' standard, so the wide fitting mainly adds midfoot room rather than toe room.

Where this data comes from

• Altra Footwear & Apparel Sizing Guide (official)
• Altra Running Size Guide, incl. +0.5cm instruction (official EU)
• Altra size chart (Marathon Sports)
• Altra Youth Size Chart (official, archived October 2023)
• Altra width options, standard and wide by gender (TopShoesReview)

Sizing information reviewed October 2026. Manufacturers revise their charts from time to time, so always confirm against the specific model before buying.

Other brand size charts