whatsizetobuy

Nike to On size conversion

Match sizes by foot length (cm), then check model fit — US labels alone can mislead across brands.

Chart match · verify brand charts
Check current prices · Air Force 1 '07 Check current prices · Cloudmonster

(paid link)

Full converter (model + shoes you own) · Reverse: On → Nike

Nike → On chart

Static conversion table (crawlable). Interactive tool above uses the same cm matching.

Nike UScmOn USOn EU
6.023.56.038.5
6.524.06.539.0
7.024.57.040.0
7.525.07.540.5
8.025.48.041.0
8.525.98.542.0
9.026.29.042.5
9.526.79.543.0
10.027.110.044.0
10.527.510.544.5
11.027.911.045.0
11.528.411.545.5
12.028.812.046.0
13.029.713.047.5

How this Nike → On chart actually maps

Nike US 10 is 27.1 cm and the nearest On US is also 10 (EU 44). The table is 1:1 from US 6 (23.5 cm) to US 13 (29.7 cm). The wear-box “Nike 10 ≈ On 10.0” is that centimeter — not a claim that Pegasus and Cloud 5 share a last. On prints EU 44 at US 10 here; Nike often prints EU 43.5 on sibling charts for the same US 10.

On’s linked models split harder than the US numbers. Cloud 5 is the snug everyday last on this site (often half up; elastic speed-lace). Cloudmonster is the more forgiving cushion trainer; Cloudsurfer sits with that roomier family. Nike’s split is the other way: AF1 '07 often half-down for length; Dunk and Pegasus stay TTS. Feeding an AF1 9.5 into Cloud 5 because the chart is 1:1 lands you short in a last that already runs small.

Convert from the Nike size that actually fits in length (Dunk/Pegasus, or 27.1 cm), then decide On from the model. If you already half-up in Cloud 5, that larger number is extra length in Cloudmonster — the wear-box on the Cloud 5 page maps Cloud 5 US 10 back to Cloudmonster 9.5. Do not stack “On runs small” on top of this 1:1 brand table. Half a size here is 26.7 → 27.1 → 27.5 cm (~4 mm of labeled length).

Model fit matters

Even when charts match, lasts differ. Check these guides:

Nike: Air Force 1 '07 · Dunk Low · Pegasus 41 · Vomero 5

On: Cloudmonster · Cloud 5 · Cloudsurfer

Also compare Nike to: Adidas · New Balance · Converse · Vans

Check prices: Nike On (paid link)

FAQ

How do I convert Nike shoe size to On?
Match by foot length in centimeters on each brand’s chart. Example: Nike US 10 ≈ On US 10.0 (about 27.1 cm). Then adjust for the specific model’s fit (runs big/small/narrow).
Is a Nike US 10 the same as a On US 10?
Not always. Labels can map to slightly different foot lengths. Use the cm column, then check model guides on both brands.
Which direction should I read first?
Start from the brand you already wear, then open the model fit pages linked below — lasts differ even when charts match.

Clothes sizing uses a separate compare path.