ReebokvsUnder Armour, Size Comparison
Under Armour tends to run smaller than Reebok. If you wear a Medium at Reebok, you may need a Large at Under Armour. For a measurement-based recommendation, use the fit checker.
Reebok vs Under Armour sizing, quick answer
Under Armour runs about one size smaller than Reebok. If you wear a Medium at Reebok, you'll likely need a Large at Under Armour. For an exact recommendation, build a free fit profile.
- Reebok: fits true to size
- Under Armour: runs small
- If between sizes: size up at the brand that runs smaller, or use the fit checker below for a personalised recommendation.
Brand guide
Compare how Reebok and Under Armour usually fit, where cuts feel slimmer or roomier, and which categories are most predictable.
GENERAL BRAND GUIDANCE
This is a general brand-level sizing summary, not an exact product recommendation. For your specific size, paste a product link into the fit checker.
The Verdict
Reebok sizing compared to Under Armour: Reebok fits true to size while Under Armour runs small. Here is how the sizes translate.
Under Armour tends to run smaller than Reebok. If you wear a Medium at Reebok, you may need a Large at Under Armour. For a measurement-based recommendation, use the fit checker.
Category Match-up
Size Conversion Table
* Indicative only. For your personalised size at both brands,
Common Questions
Does Reebok run smaller than Under Armour?
Under Armour runs about one size smaller than Reebok. If you wear a Medium at Reebok, you'll likely need a Large at Under Armour. For an exact recommendation, build a free fit profile.
Should I size up or down at Reebok vs Under Armour?
Size up one at Under Armour compared to Reebok. Under Armour runs smaller, so if you wear a Medium at Reebok, try a Large at Under Armour, especially for fitted tops and tailored bottoms.
If I'm a Medium at Reebok, what size am I at Under Armour?
Since Under Armour runs smaller than Reebok, a Medium at Reebok is roughly equivalent to a Large at Under Armour. Use the ThisFits fit checker for a recommendation based on your measurements.
Does Reebok or Under Armour fit differently by category?
Yes, fit varies meaningfully by category. Tops, Bottoms can each fit differently than the brand's overall tendency suggests. See the Category Match-up section below for per-category guidance.
Which brand is more accurate to its size chart, Reebok or Under Armour?
Reebok and Under Armour both publish official size charts, but real-world fit varies by fabric, cut and category. The ThisFits engine cross-references published charts with shopper fit reports across 197+ brands to predict your size in each.
What if I'm between sizes at Reebok and Under Armour?
If you're between sizes, Under Armour tends to fit closer to the body, so trying the larger size first usually means fewer returns. Always confirm each retailer's return policy before ordering.