Blundstone Size Chart: AU/UK to US and EU, Foot Length in mm and Half-Size Rules

Blundstone’s sizing has a quirk that catches most first-time buyers: the number stamped on the sole is an AU/UK size, but US customers order in a US size and the boot arrives in the matching AU/UK size. Blundstone’s own example makes the point. A boot stamped 8 is a men’s US 9 or a women’s US 11. And its chart goes further than most brands: it gives foot length in millimeters, it says half sizes add width but not length, and it publishes separate kids’ and women’s safety charts. This guide reproduces those charts from Blundstone’s official pages, then explains the parts that are easy to get wrong: what a half size really changes, which series fit differently, and why three regional Blundstone pages give slightly different advice on toe room and on the Dress Series.

Start With the Number on the Sole

Every Blundstone has an AU/UK size stamped on the bottom. That number is the one the boot is really made in, and it is the one to use when you are comparing a new pair with an old pair, buying insoles, or contacting customer service. Blundstone’s US page puts it simply: order in US size, and the boot ships in the corresponding AU/UK size shown on the sole.

Blundstone’s own sole example shows how big the gap is: AU/UK 8 equals men’s US 9, or women’s US 11. So a US men’s 9 wearer who flips a pair over and sees an 8 is not looking at a mistake, and a US women’s 8 wearer should expect a 5 on the sole. The charts below spell out every pair. Because the unisex sizes are men’s sizes in the UK, a woman buying a classic Blundstone is buying a unisex boot, not a women’s last, and Blundstone’s women’s series are listed separately.

Blundstone Adult Unisex Size Chart (AU/UK, US Men’s, EU, mm)

This is Blundstone’s adult unisex chart from its Australian size guide, with the men’s US column. Blundstone’s adult lifestyle boots are sold in unisex sizes, so this is the chart to use for most styles. Note the pairs of half sizes that share a foot length: AU/UK 3 and 3.5 are both 220 mm, 4 and 4.5 are both 228 mm, and so on. We explain why below. For the general men’s scale, see our men’s shoe size chart.

Source: Blundstone Australia size guide, adult unisex sizes.

Blundstone Women’s Size Chart (US Women’s, AU/UK, EU, mm)

The same adult chart has a US women’s row, but it stops at US 12, and the box under AU/UK 8.5 is crossed out, so it has no women’s equivalent. We show only the sizes Blundstone lists. For the general women’s scale, see our women’s shoe size chart.

Source: Blundstone Australia size guide, adult unisex sizes. AU/UK 8.5 has no US women’s size on the chart.

Half Sizes Add Width, Not Length

This is the single most useful fact in Blundstone’s guide, and it is stated plainly on both its Australian and US pages. When you buy a half size, the footbed is exactly the same size as the whole size below it. The difference is a little more leather in the upper, which gives extra room for a wider foot. You can see it in the chart: AU/UK 8 and 8.5 are both 262 mm, and AU/UK 9 and 9.5 are both 271 mm.

So the rule Blundstone gives is simple. If you want a wider fit, go up a half size. If you need more length, go up a full size. A half size will not help a boot that is too short, and a full size when you only needed width can leave your heel slipping. Blundstone’s UK page puts it the same way: half sizes increase width, not length. If you fall between sizes by length, measure your longer foot in millimeters and use the chart. If you fall between sizes by width, try the half size.

How to Find Your Size From a Foot Measurement

Blundstone’s Australian guide gives a two step method. First, stand barefoot on a piece of paper, mark where your longest toe ends, and measure from the back of your heel to the tip of your longest toe in millimeters. Do it for both feet and use the larger number to find your size on the chart above. Second, decide whether you need width: if you do, go up a half size.

An example. A foot measuring 258 mm falls between 254 mm (AU/UK 7 or 7.5, men’s US 8 or 8.5) and 262 mm (AU/UK 8 or 8.5, men’s US 9 or 9.5). The longer size is the right choice for length, since the boot will not stretch lengthwise. If that foot is also wide, the half size in that length is the next thing to try. For a step by step guide to measuring, see our guide to measuring your foot at home.

Fit by Series: Originals, Classics, Dress, Women’s and Thermal

Blundstone says its range includes different lasts, lacing systems and upper types, so fit varies by series. Here is what its pages say. The UK page is the most detailed, and the US and Australian pages agree on the main points.

• Originals: firm across the top and toe, and they often run true to size. The thick leather softens over time. Vegan, kids and women’s high-top styles are described the same way.
• Classics: a slightly wider fit than the Originals, relaxed across the top and toe, with a leather lining and an extra pair of footbeds to adjust fit.
• All-Terrain: a relaxed fit with a Vibram sole.
• Dress Series (chisel toe): a slightly longer, roomier fit with an elongated toe box. Some people go down a half size, and the UK page says you may want to go down a size.
• Dress ankle boots (men’s): a slimmer, tapered fit with a longer toe box. Blundstone’s UK page suggests considering a half or full size down.
• Women’s Series: narrower and closer fitting than the unisex boots. If you need a wider fit, go up half a size.
• Thermal Series: relaxed like the Classics but snugger, because the sheepskin footbed compresses over time.
• Originals shoes: true to size, with a half size up for a wider fit.

None of this is a guarantee for your foot, but it gives you a direction before you order. If you are buying a Dress boot for the first time, expect to try one size smaller than you wear in an Original, and check the return window.

Three Blundstone Pages, Three Slightly Different Answers

Blundstone runs separate sites for the US, Australia and the UK, and the fit advice on them is similar but not identical. We read all three. The differences matter if you are choosing a size at the edge of the range.

Source: Blundstone US, Australia and UK size guides as read on October 31, 2026.

The toe room figures work out to about 6 mm, 5 mm and 10 mm. That is a spread of about 5 mm, which is not nothing in a boot that will not stretch in length. A safe reading is to aim for a small, definite gap, not a tight fit and not a roomy one. Use the stand and wiggle test below to check it. On the Dress Series, the three pages move from “some people go down a half size” to “you may want to go down a size,” so the more cautious read is to try both a half size and a full size down, and see which one gives you a heel that stays put.

Blundstone Kids’ Size Chart

Blundstone’s kids’ chart uses its own numbering, from 7 up to 13 and then 1 to 3, with foot length in millimeters and EU. There is no US column on the chart we read. All of Blundstone’s kids’ styles have a removable insole, which helps you adjust the fit as feet grow.

Source: Blundstone Australia size guide, kids’ sizes.

Measure your child’s longer foot in the socks they will wear, and compare the number with the foot length row. Allow some room for growth, which the removable insole helps with. For general kids’ conversions, see our kids’ shoe size chart.

Women’s Safety Sizes

Blundstone’s women’s safety boots use their own chart. Its numbers follow the US women’s numbering on the adult chart rather than the AU/UK numbering: a women’s safety 8 has a foot length of 237 mm, the same as the adult chart’s US women’s 8, which is AU/UK 5.

Source: Blundstone Australia size guide, women’s safety sizes.

The EU numbers are not identical to the adult chart at every size. Women’s safety 6 and 6.5 list EU 36 and 36.5, while the adult chart’s US women’s 6 and 6.5 list EU 35.5 and 36. We show both as published. If you are buying a safety boot, use this chart, not the adult chart with an AU/UK number.

Sizing for Winter, Socks and Thermal Boots

Blundstone has a winter sizing guide on its US site. It says your feet may need a boot a half size, or even a whole size, larger than your shoe size, because you want a snug fit with room for your feet to spread during the day. Too tight leaves feet cold with no toe room, and too loose risks heel blisters. It recommends trying boots on with the socks you will wear in them: Blundstone merino wool socks, or a thick pair of your own. It says to avoid cotton, which keeps the cold in.

For the Thermal Series specifically, the guide says the boots fit true to size, and that if your feet are wider than average you should go up a half size. Given Blundstone’s other statement that half sizes add width and not length, that is the width answer, not a length answer.

Three Quick Fit Tests From Blundstone

Blundstone’s winter guide describes three tests you can do at home with laced boots on. The kick test: gently kick a wall, and if your toes hit the end, try a smaller size. The heel test: if two fingers do not fit behind your heel, go larger, and if there is a lot of extra room, go smaller. The toe test: stand and wiggle your toes, and if you feel pressure on the toes or at the widest part of the foot, try a larger size. Blundstone’s size guides add that a slight give at the heel is normal in new boots, and that you should try them on standing, on a carpeted surface to protect the soles.

One caution: the kick test and the heel test point in opposite directions if you misread them. Use them together. A boot that passes the toe test and has a snug heel is closer to right than one that passes only one of them.

Insoles, Extra Footbeds and Trimming

Classic Series boots come with extra insoles to adjust fit, and kids’ styles have a removable insole. Blundstone also sells insoles separately in Comfort Classic, Comfort Arch and sheepskin versions, compatible with most adult styles. Its guide says to order the insole with the same number as your boot, converting the AU/UK number on the sole to US size, and that insoles are unisex. If sizes are listed as a range, pick the range that includes your size and trim to fit.

To trim, remove the worn insole, lay it on top of the new one, trace its outline, and cut slightly outside the line, since you can always trim more. You can also use the guideline printed on the bottom of the insole. This is useful for a boot that is a touch roomy: a thicker footbed can take up some volume, though it will not fix a boot that is too long.

Blundstone’s True Fit Tool and Existing Pairs

Blundstone’s site has a size tool called True Fit on every product page. It uses your height, weight, age, foot shape, the brands and sizes you wear and whether you like a snug or roomy fit. Blundstone says it is more accurate than a size chart for many customers, and recommends following it if you are unsure. We cannot verify that claim, but the tool is free and it accounts for the style you are viewing, so it is a sensible second opinion. If you already own Blundstones that fit well, Blundstone generally recommends ordering the same US size.

Returns and Break-In

Blundstone’s US and Australian pages say purchases must be returned within 30 days from the date of purchase or order. Check the current policy before you buy, since it can change. For break-in, the UK page says smooth premium leather feels tighter at first and needs a few wears, nubuck is slightly thicker and may need a longer break-in, and waxed suede may feel stiff at first but softens. All the pages agree that the boot stretches slightly over the instep but never in length.

Comparing Blundstone With Other Boot Brands

Blundstone’s numbering is the odd one out, so do not move a size across by number. A men’s US 9 in a Blundstone is an AU/UK 8 on the sole. If you wear Dr. Martens, Clarks, UGG or Red Wing, start from your measured foot in millimeters and read across to the chart above. Blundstone’s foot length row is the easiest bridge.

Blundstone Sizing: Questions People Ask

A Short Routine for Choosing Your Blundstone Size

Blundstone sizing comes down to three decisions. Convert from the number on the sole using the chart, choose length from your longer foot in millimeters, and then decide on width. Go up a half size for width, a full size for length, and check the series, because the Dress and Women’s styles fit differently from the Originals.

More Boot Size Guides

Sources

• Blundstone Australia size guide
• Blundstone US size guide
• Blundstone UK size guide
• Blundstone help: What size boots should I order?
• Blundstone winter boot sizing guide
• Blundstone insoles sizing and trimming guide
• Blundstone True Fit guide