ASICS Novablast 6

Does the ASICS Novablast 6 run true to size? Should you size up?

We checked, on 16,874 real feet. We worked out the inside measurements of the ASICS Novablast 6 Men's / Unisex in the standard width: the length, the width, and the forefoot volume (ball girth). Then we virtually fitted 16,874 real feet from our earlier in-store 3D foot scanners, the way a runner shopping online would: ASICS's size chart, including ASICS's note to go half a size up.

Does the ASICS Novablast 6 run true to size?

For less than half of feet. If you follow ASICS's size guidance online, the Novablast 6 fits true to size for 46% of feet. Here, true to size means the size ASICS's online guidance gives you is less than a full size away from the size that fits best, with enough toe room and enough room in the forefoot area.

ASICS's size guidance gets the length right: with the note to go half a size up, the size chart gives almost every foot enough length. The guidance falls short on the forefoot area. ASICS makes a wide version of the Novablast 6, but ASICS's size guidance online gives shoppers no way to find out whether they need the wide version, so our score uses only the standard width. If ASICS's guidance showed shoppers how to pick between standard and wide, the score would have been 67.

Should you size up or down in the ASICS Novablast 6?

Here is where every foot landed when we followed ASICS's size chart in the standard width.

Share of 16,874 feet. Each foot is counted once.

• Right size from the size chart: 46% of feet got a size that fit both their length and their forefoot area in the standard width. If you are in this group, buy the size ASICS's guidance gives you, half a size up included.
• Sized up for more room in the forefoot area: 33% of feet were too tight in the forefoot area of the standard width, at the size the chart gave. In the standard width, going up a size was the only way to get more room, and the bigger size also adds length in front of the toes and room for the heel to slip. The wide version adds room in the forefoot area and keeps the length, if you already know you need a wide width.
• Sized up for toe room only: Almost no feet landed here: 31 of 16,874, which rounds to 0%. With the half size up, ASICS's size chart leaves almost every foot enough room in front of the toes.
• Sized down for less room in the forefoot area: 21% of feet had too much room in the forefoot area of the standard width. The Novablast 6 has no narrow version, so a smaller size was the only way to get a snugger forefoot area. Because ASICS's note adds half a size of length, nearly all of these feet (3,550 of 3,562) still fit inside a size smaller than ASICS's guidance gave, but with less room in front of the toes.

Does the ASICS Novablast 6 come in wide and narrow widths?

The Novablast 6 comes in standard and wide, with no narrow version. ASICS's size guidance online gives no way to find your width, so choosing between standard and wide means guessing, unless you already know you need a wide width from other shoes. Runners with too much room in the forefoot area of the standard width have no narrower version to choose.

Will your heel slip in the ASICS Novablast 6?

It depends on where your foot bends, more than on your size. A shoe bends at one spot called the flex point (usually at the widest part of the shoe), and your foot bends at its ball joint.

When there is room in front of the toes (and there should be), your foot slides forward a little until the ball joint settles at the flex point. When the ball of your foot sits closer to your heel than the shoe's flex point does, your foot keeps sliding forward until the ball joint and the flex point are aligned. That leaves a gap behind your heel, so your heel can lift out of the back of the shoe more easily. That is why a heel can slip even in a size that fits the length and the forefoot area.

The Novablast 6 has a good amount of foam padding around the top edge of the heel counter that holds the heel in place. Some running shoes have the foam padding low in the heel counter, which holds the heel down more firmly, but the padding around the top edge can still reduce the risk of heel slip. A heel lock lacing can also help.

(MatchUp's shoe fitting checks your arch length against the shoe's flex point, so you can be aware of potential heel slip before you choose a size.)

How will the ASICS Novablast 6 fit your feet?

Those were 16,874 other people's feet. Where do yours fall? Only a foot scan can tell. MatchUp's shoe fitting scans your feet with your phone and a sheet of paper. The fitting checks more than length: it looks at width, ball girth, and how your arch length lines up with each shoe's flex point. Then it ranks running shoes by how well each shoe fits your foot shape, and shows how each size of the ASICS Novablast 6 will fit, so you choose the size you want. Answer a few questions about how you run, and you also get a personalized fit guide with advice for your feet, like lacing techniques for your foot shape.

Get fitted

Free, nothing to install. You need a phone and a sheet of paper.

How we measured

We measured the standard width of the Novablast 6 and virtually fitted 16,874 real feet from our earlier in-store 3D foot scanners. Out of 17,311 foot scans, those 16,874 feet fall in the Novablast 6's size range (US men's 4 to 15). For every foot, we followed ASICS's size guidance online: the length chart, including ASICS's note to go half a size up, in the standard width. A difference of a full size or more between ASICS's size and the size that fits best counts as a miss. These numbers show how the Novablast 6 fits a large group of feet, not how the shoe feels on a run.