ShoesOnCloudsurfer MAX

On

On Cloudsurfer MAX

On Cloudsurfer MAX. 37.3mm stack, 292g. Retailer specs verified on Running Warehouse.

PR Run Verified
Soft trailsLong ultrasDaily training

PR Run scores

Grip3/5
Cushion5/5
Protection3/5
Durability3/5
Versatility3/5

PR Run derived fit scores

84Elite

100-miler readiness

Will this shoe survive a hundred-mile night? 37.3 mm stack, cushion 5/5

97Elite

Descent tolerance

Does it save your toenails on long descents? 29.4 mm forefoot, heel counter 3/5

100Elite

Swelling room

Room to grow when your feet swell? 26.2 mm toebox height

71Great

Grit resistance

Does dust stay outside the shoe? 2 BR breathability

22Weak

Hot-day comfort

How well does it breathe in heat? 2 BR / ?% drying

63Solid

Achilles-friendly

Kind to a cranky achilles? 7.9 mm drop, heel counter 3/5

Full specs

Drop

7.9 mm

Heel stack

37.3 mm

Forefoot stack

29.4 mm

Weight

292 g

Plate

No

Waterproof

No

Lab measurements

MeasurementValue
Traction (CoF)0.53
Breathability2 BR
Flexibility18.2 N
Torsional rigidity14.20 Nm
Heel counter3/5
Energy return48.3 %
Shock absorption141 SA
Midsole softness43.8 HA
Outsole thickness3.2 mm
Tongue padding1.5 mm
Insole removableYes
Insole thickness3.1 mm
Reflective elementsNo

Lab numbers from RunRepeat. Sources.

Fit intelligence

Toebox width

Narrow toebox (71.4 mm vs 96 mm median)

Toebox height

Slightly tall (26.2 mm vs 25 mm median)

True to size.

Fit numbers from the lab. Swell guidance: foot care.

Questions before you race

Is the On Cloudsurfer MAX good for 100-mile races?

Elite. 37.3 mm stack, cushion 5/5. 100-miler readiness score 84/100.

Does the On Cloudsurfer MAX fit wide feet?

No. Toebox is 71.4 mm which is narrow. Look elsewhere if you need width.

What is the drop on the On Cloudsurfer MAX?

7.9 mm, with a 37.3 mm heel stack and 29.4 mm forefoot.

Is the On Cloudsurfer MAX good on wet rock?

Traction coefficient of friction on wet lab surface: 0.53. Solid grip on wet rock.

Manufacturer specs · Retailer listing

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Image: Running Warehouse product photo

Specs: manufacturer. Verified Sep 4, 2026.

Report inaccurate data: hi@pr.run. Data sources.

On Cloudsurfer MAX Review, Specs, and Fit (2026) | PR Run