On
On Cloudswift 4
On Cloudswift 4. 32.7mm stack, 291g. Retailer specs verified on Running Warehouse.
PR Run scores
PR Run derived fit scores
100-miler readiness
Will this shoe survive a hundred-mile night? 32.7 mm stack, cushion 4/5
Descent tolerance
Does it save your toenails on long descents? 22.3 mm forefoot, heel counter 2/5
Swelling room
Room to grow when your feet swell? 33.5 mm toebox height
Grit resistance
Does dust stay outside the shoe? 4 BR breathability
Hot-day comfort
How well does it breathe in heat? 4 BR / ?% drying
Achilles-friendly
Kind to a cranky achilles? 10.4 mm drop, heel counter 2/5
Full specs
Drop
10.4 mm
Heel stack
32.7 mm
Forefoot stack
22.3 mm
Weight
291 g
Plate
No
Waterproof
No
Lab measurements
| Measurement | Value |
|---|---|
| Traction (CoF) | 0.52 |
| Breathability | 4 BR |
| Flexibility | 10.7 N |
| Torsional rigidity | 15.80 Nm |
| Heel counter | 2/5 |
| Energy return | 57.6 % |
| Shock absorption | 128 SA |
| Midsole softness | 51.3 HA |
| Outsole thickness | 3.5 mm |
| Tongue padding | 1.6 mm |
| Insole removable | Yes |
| Insole thickness | 4.2 mm |
| Reflective elements | Yes |
Fit intelligence
Toebox width
Narrow toebox (68.9 mm vs 96 mm median)
Toebox height
Tall toebox (33.5 mm vs 25 mm median)
True to size.
Fit numbers from the lab. Swell guidance: foot care.
Questions before you race
Is the On Cloudswift 4 good for 100-mile races?
Great. 32.7 mm stack, cushion 4/5. 100-miler readiness score 78/100.
Does the On Cloudswift 4 fit wide feet?
No. Toebox is 68.9 mm which is narrow. Look elsewhere if you need width.
What is the drop on the On Cloudswift 4?
10.4 mm, with a 32.7 mm heel stack and 22.3 mm forefoot.
Is the On Cloudswift 4 good on wet rock?
Traction coefficient of friction on wet lab surface: 0.52. Solid grip on wet rock.
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swellingRoom: 100/100 (Elite)
descentTolerance: 100/100 (Elite)
gritIngressRisk: 70/100 (Great)
hotFootScore: 23/100 (Weak)
achillesFriendlyScore: 58/100 (Solid)
hundredMilerReadiness: 78/100 (Great)