On Cloudmonster 1 Men's

For a little over half of feet. If you follow On's size guidance online, the Cloudmonster 1 Men's fits true to size for 54% of feet. Here, true to size means the size On's online guidance gives you is less than a full size away from the size that fits best, with enough toe room and enough forefoot volume.

On's US product page for the Cloudmonster 1 Men's says "True to size," and On's US size chart converts US sizes to other countries' sizes but lists no foot length. For our fittings, we used the Japanese sizes in On's chart as foot lengths, because Japanese shoe sizes are defined by foot length in centimeters. The Cloudmonster 1 Men's comes in one width, so a different size is the only way to change the forefoot volume. In our fittings, most of the misses came from feet that needed more forefoot volume.

Here is where every foot landed in the Cloudmonster 1 Men's when we followed On's size chart.

Share of 8,016 feet. Each foot is counted once.

• Right size from the size chart: 54% of feet got a size that fit both their foot length and their forefoot volume. On's size chart worked well for this group in the Cloudmonster 1 Men's.
• Sized up for more forefoot volume: For 36% of feet, the Cloudmonster 1 Men's had too little forefoot volume at the size the chart gave. The Cloudmonster 1 Men's has no wide version, so going up a size was the only way to get more forefoot volume, and the bigger size also adds length in front of the toes.
• Sized up for toe room only: 10% of feet had enough forefoot volume, but the length the chart gave left their toes very little room. If your foot is near the long end of your size on On's chart, consider half a size up in the Cloudmonster 1 Men's.
• Sized down for less forefoot volume: Almost no feet landed here: 35 of 8,016, which rounds to 0%. At the size On's chart gave, the Cloudmonster 1 Men's had enough forefoot volume for almost every foot that wasn't too short for it.

We measured the Cloudmonster 1 Men's, which comes in one width, and virtually fitted 8,016 real feet from our earlier in-store 3D foot scanners. Out of 17,311 foot scans, those 8,016 feet fall in the size range of the Cloudmonster 1 Men's (US men's 7 to 14). For every foot, we followed On's size guidance: the length chart, using the Japanese sizes in On's US size chart as foot lengths, in the standard width. A difference of a full size or more between On's size and the size that fits best counts as a miss. These numbers show how the Cloudmonster 1 Men's fits a large group of feet, not how the shoe feels on a run.