Nike vs adidas Sizing: How Do Their Shoes Compare?

Nike's Swoosh in white vs. the adidas three stripe logo in white with white shoes from each brand behind them but blurry.
Connor Groom
By Connor Groom

Nike's Swoosh in white vs. the adidas three stripe logo in white with white shoes from each brand behind them but blurry.

Getting the right fit is crucial when shopping for sneakers online, especially when you’re choosing between two giants like Nike and adidas.

We’ve all been there: you unbox a fresh pair of shoes, only to realize they’re either too tight or way too roomy. Fortunately, this guide breaks down the key Nike vs. adidas sizing differences, helping you confidently choose the right size before you buy.

How Should Sneakers Fit?

Before comparing brands, it’s important to understand how sneakers should fit for both comfort and performance, much like when comparing ASICS and New Balance.

According to Nike, it's as follows:

General Fit Guidelines

  • Toe Room – Your toes should have enough space to wiggle freely to avoid irritation and pressure points.
  • Heel Fit – Your heel should feel secure without slipping. Excess movement can lead to discomfort and blisters.
  • Length Check – Clarks recommends leaving about a thumb’s width of space between your longest toe and the end of the shoe when standing.
  • Natural Bend Point – The shoe should flex at the ball of your foot, not in the middle of the arch. This is especially important for running and gym trainers.

These rules apply across most sneaker types, from performance models like the Nike Alphafly 3 to lifestyle favorites like the adidas Ultraboost.

Nike vs. adidas Size Comparison

Although both brands use standard size charts, Nike and adidas sneakers fit differently, making it important to double-check sizing before purchasing.

Nike size chart compared to adidas' size chart for shoes.
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adidas shoes run smaller than Nikes.

Key Sizing Differences

  • Nike sneakers generally fit true to size
  • adidas sneakers tend to feel slightly smaller and shorter
  • In EU sizing, a Nike EU 44 fits closer to a true full size, while an adidas EU 44 may feel slightly shorter
  • If you’re between sizes, going half a size up in adidas is often the safer choice

Nike vs. adidas Width Comparison

Length isn’t everything, as width plays a major role in overall comfort.

Nike Width Options

Nike provides detailed width charts, helping shoppers identify wide and extra-wide fits. For example:

  • A Men’s US 10 foot measuring 4.2 inches (10.67 cm) is classified as wide
Nike width chart's for men and women shoes.
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Nike has a handy width chart to compare your shoe size to.

adidas Width Options

adidas offers less detailed width guidance, which can make sizing trickier. However, general width standards still apply:

Men’s US 8 Width Guide

  • B – Approx. 8.73 cm
  • D – Approx. 9.68 cm (standard)
  • 2E – Approx. 10.64 cm (wide)
  • 4E – Approx. 11.59 cm (extra wide)

Which Nike and adidas Shoes Fit Wide Feet?

If you have wide feet, choosing the right model matters just as much as picking the right size.

Best Nike Shoes for Wide Feet

Best adidas Shoes for Wide Feet

adidas also offers a selection of wide-fit shoes, particularly in categories like:

While not every adidas model comes in a wide version, there are plenty of options worth exploring.

Overall verdict: Nike tends to feel slightly roomier by default, especially in length, making it a better option for many wide-foot wearers.

Which Nike and adidas Shoes Run Narrow?

Some sneakers are intentionally designed with a snug, performance-first fit.

adidas Shoes That Run Narrow

Nike Shoes That Run Narrow

  • Nike Flyknit sneakers – The fabric molds closely to the foot, giving a slightly tighter fit based on feel.
  • Nike Free series – Features internal webbing for a more locked-in, tighter fit.
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Image from Nike vs adidas Sizing: How Do Their Shoes Compare?

Running Shoes

Running shoes tend to fit narrower, so if you need a tighter fit, check out the running ranges from either brand here.

Shop Running at NikeShop Running at adidas

Final Thoughts

When choosing between Nike vs adidas sizing, keep these key points in mind:

  • Nike sneakers typically fit true to size
  • adidas sneakers often run slightly smaller
  • Both brands offer wide-fit options, though Nike provides clearer guidance
  • Performance shoes usually fit narrower, while lifestyle and basketball models offer more room

If possible, try on sneakers in-store. If not, this guide should help you make a confident, informed decision online.

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