Nike and Adidas are the two biggest sportswear brands in the world, and one of the most common questions shoppers ask is: "Should I buy the same size in both brands?"

The short answer: mostly yes, but there are important nuances.

Nike Sizing Overview

Nike generally runs **true to size** for most of their products. Their size charts are consistent across most product lines, from Dri-FIT tees to hoodies to jackets.

**Nike Men's Tops Size Chart (cm)**

Adidas Sizing Overview

Adidas also runs **true to size**, but their European sizing baseline means some items may fit slightly differently than Nike equivalents.

**Adidas Men's Tops Size Chart (cm)**

Key Differences

Fit Philosophy

Nike Generally offers a slightly more athletic cut — narrower in the waist, broader in the shoulders

Adidas Tends toward a more relaxed, European cut — slightly roomier overall

Size-for-Size Comparison

If you wear a size M in Nike tops, you'll likely wear a size M in Adidas too. However:

If you're at the top of the size range Nike M (97cm chest max) vs Adidas M (98cm max) — Adidas gives you 1cm more room

Slim fit items Nike's "slim fit" is noticeably slimmer than Adidas's "slim fit"

What Customers Say

Based on thousands of customer reviews:

Nike 78% of customers say Nike runs "true to size," 12% say "runs small," 10% say "runs large"

Adidas 75% of customers say Adidas runs "true to size," 8% say "runs small," 17% say "runs large"

The Verdict

**For most people, buying the same size in both brands will work.** If you're between sizes or prefer a specific fit:

Size up for Nike if you're between sizes (Nike athletic cuts can be snug)

Your regular size is fine for Adidas (more forgiving fit)

Get Your Exact Measurements

Don't guess — use BodySize AI to measure your body from a photo. Once you have your exact measurements, check our Nike and Adidas size charts for your recommended size.

Nike Size Guide vs Adidas: Which Brand Runs True to Size?