Sizing guide Updated

New Balance FuelCell Supercomp Trainer v3 Sizing Guide: Does It Run Small or True to Size?

Short answer

The New Balance FuelCell Supercomp Trainer v3 is a high-stack, carbon-plated powerhouse featuring a revamped 20% PEBA-blend FuelCell midsole and proprietary Energy Arc technology. This 'super trainer' delivers a snappy and propulsive ride, though its architectural shift toward a performance last results in a snug fit with reduced vertical volume in the toe box.

Runs true to size

Cross-sizing: what size to buy

Find a shoe you already own and read across to the New Balance FuelCell Supercomp Trainer v3 size to buy.

  • Nike Air Force 1

    Your usual Buy
    US 9.5 10.5
    EU 43 44.5

  • ASICS Superblast 2

    Your usual Buy
    US 10 10.5
    EU 44 44.5

  • New Balance 990v6

    Your usual Buy
    US 10 10.5
    EU 44 44.5

  • Adidas Samba

    Your usual Buy
    US 10 10.5
    EU 44 44.5

Fit Notes

Nike Air Force 1
The Air Force 1 is a high-volume lifestyle shoe that notoriously fits large, typically requiring users to size down 0.5. Conversely, the SC Trainer v3 is a low-volume performance model with a tapered toe box. To accommodate the length reduction and aggressive rocker geometry, you must size up 1.0 full size from your AF1 baseline.
ASICS Superblast 2
The Superblast 2 features a more voluminous and forgiving internal cavity. In comparison, the SC Trainer v3 feels significantly more compressed and runs shorter in internal length. Sizing up 0.5 from your Superblast size is recommended to prevent distal pressure on the toes during high-mileage training.
New Balance 990v6
Heritage 'Made in USA' models like the 990v6 are engineered with far more internal room than the FuelCell performance line. Because the SC Trainer v3 utilizes a more restrictive, tapered last designed for lockdown, a 0.5 size increase is mandatory to match the length comfort of the 990.
Adidas Samba
While the Samba has a slim silhouette, the SC Trainer v3's structured upper and integrated carbon plate require more 'buffer' room at the front of the shoe. Additionally, the rocker geometry pushes the foot forward during movement, necessitating a 0.5 size increase from the Samba to avoid toe bruising.

Sizing FAQ

Does the New Balance FuelCell Supercomp Trainer v3 run true to size?

No, the general consensus is that the SC Trainer v3 runs slightly small. Approximately 60-70% of runners recommend moving up a half-size (0.5 US) from your standard measurement to compensate for the tapered toe box and the forward-leaning rocker geometry.

Is the New Balance FuelCell Supercomp Trainer v3 good for wide feet?

The standard 'D' width is reported as too restrictive for wide or high-volume feet due to a lack of vertical wiggle room and lateral stretch in the FANTOMFIT upper. Wide-footed users should utilize the dedicated 2E width option in their standard size rather than simply sizing up in length, which may result in poor lockdown.

How is the arch support on the New Balance FuelCell Supercomp Trainer v3?

The SC Trainer v3 provides a secure, neutral wrap around the longitudinal arch through its gusseted tongue and FANTOMFIT overlays. While it lacks a medial post, the wide forefoot base and forked carbon fiber plate offer 'inherent stability' that resists lateral spilling, making it suitable for neutral runners and mild overpronators.

Specs & Sizing

Weight 248 g
Retail price $169
Price on Amazon $149–$179
Release year 2025
Upper Engineered mesh with synthetic overlays for secure lockdown and moderate breathability
Midsole FuelCell foam with 3% bio-based content, tuned for propulsion and responsiveness
Outsole Durable rubber with strategic traction zones; moderate grip on dry pavement, limited data on wet conditions
Technologies FuelCell foam, Energy Arc plate under forefoot, 4mm heel-to-toe drop
Fit & sizing True to size for standard foot shapes; narrow-footed users may prefer regular width, wide-footed may need EE option